WorldWideScience

Sample records for level scheme nuclear

  1. Statistical interpretation of low energy nuclear level schemes

    Energy Technology Data Exchange (ETDEWEB)

    Egidy, T von; Schmidt, H H; Behkami, A N

    1988-01-01

    Nuclear level schemes and neutron resonance spacings yield information on level densities and level spacing distributions. A total of 75 nuclear level schemes with 1761 levels and known spins and parities was investigated. The A-dependence of level density parameters is discussed. The spacing distributions of levels near the groundstate indicate transitional character between regular and chaotic properties while chaos dominates near the neutron binding energy.

  2. Gamma spectrometry; level schemes

    International Nuclear Information System (INIS)

    Blachot, J.; Bocquet, J.P.; Monnand, E.; Schussler, F.

    1977-01-01

    The research presented dealt with: a new beta emitter, isomer of 131 Sn; the 136 I levels fed through the radioactive decay of 136 Te (20.9s); the A=145 chain (β decay of Ba, La and Ce, and level schemes for 145 La, 145 Ce, 145 Pr); the A=47 chain (La and Ce, β decay, and the level schemes of 147 Ce and 147 Pr) [fr

  3. On 165Ho level scheme

    International Nuclear Information System (INIS)

    Ardisson, Claire; Ardisson, Gerard.

    1976-01-01

    A 165 Ho level scheme was constructed which led to the interpretation of sixty γ rays belonging to the decay of 165 Dy. A new 702.9keV level was identified to be the 5/2 - member of the 1/2 ) 7541{ Nilsson orbit. )] [fr

  4. LevelScheme: A level scheme drawing and scientific figure preparation system for Mathematica

    Science.gov (United States)

    Caprio, M. A.

    2005-09-01

    LevelScheme is a scientific figure preparation system for Mathematica. The main emphasis is upon the construction of level schemes, or level energy diagrams, as used in nuclear, atomic, molecular, and hadronic physics. LevelScheme also provides a general infrastructure for the preparation of publication-quality figures, including support for multipanel and inset plotting, customizable tick mark generation, and various drawing and labeling tasks. Coupled with Mathematica's plotting functions and powerful programming language, LevelScheme provides a flexible system for the creation of figures combining diagrams, mathematical plots, and data plots. Program summaryTitle of program:LevelScheme Catalogue identifier:ADVZ Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVZ Operating systems:Any which supports Mathematica; tested under Microsoft Windows XP, Macintosh OS X, and Linux Programming language used:Mathematica 4 Number of bytes in distributed program, including test and documentation:3 051 807 Distribution format:tar.gz Nature of problem:Creation of level scheme diagrams. Creation of publication-quality multipart figures incorporating diagrams and plots. Method of solution:A set of Mathematica packages has been developed, providing a library of level scheme drawing objects, tools for figure construction and labeling, and control code for producing the graphics.

  5. Present and future nuclear power financing schemes

    International Nuclear Information System (INIS)

    Diel, R.

    1977-01-01

    The financial requirement for nuclear power plants in the Federal Republic of Germany for the period up until 1985 was estimated to run up to some DM 100 billion already in the Nuclear Energy Study published by the Dresdner Bank in 1974. This figure is not changed in any way by the reduction the nuclear power program has suffered in the meantime, because the lower requirement for investment capital is more than offset by the price increases that have occurred meanwhile. A capital requirement in the order of DM 100 billion raises major problems for the power producing industry and the banks which, however, are not going to hamper the further expansion of nuclear power, because new financing schemes have been specially developed for the nuclear field. They include financing by leasing, the use of funds from real estate credit institutions for long term financing, borrowing of long term funds in the Euro market, and financing through subsidiaries of the utilities. The new financing schemes also apply to the large financial requirement associated with the nuclear fuel cycle, waste management in particular. In this sector the utilities agree to bear the economic risk of the companies implementing the respective projects. Accordingly, financing will not entail any major difficulties. Another area of great importance is export financing. The German-Brazilian nuclear agreement is a model of this instrument. (orig.) [de

  6. Level Scheme of 223Fr

    International Nuclear Information System (INIS)

    Gaeta, R.; Gonzalez, J.A.; Gonzalez, L.; Roldan, C.

    1972-01-01

    A study has been made of the decay of 2 27 Ac at levels of 223 F r, means of alpha Spectrometers of Si barrier detector and gamma Spectrometers of Ge(Li). The rotational bands 1/2-(541 ↓ ] , 1/2-(530 ↑ ) and 3/2-(532 ↓ ) have been identified, as well as two octupolar bands associated with the fundamental one. The results obtained indicate that the unified model is applicable in this intermediate zone of the nuclide chart. (Author) 150 refs

  7. Nuclear Level Densities

    International Nuclear Information System (INIS)

    Grimes, S.M.

    2005-01-01

    Recent research in the area of nuclear level densities is reviewed. The current interest in nuclear astrophysics and in structure of nuclei off of the line of stability has led to the development of radioactive beam facilities with larger machines currently being planned. Nuclear level densities for the systems used to produce the radioactive beams influence substantially the production rates of these beams. The modification of level-density parameters near the drip lines would also affect nucleosynthesis rates and abundances

  8. ZZ-CENPL, Chinese Evaluated Nuclear Parameter Library. ZZ CENPL-DLS, Discrete Level Schemes and Gamma Branching Ratios Library; ZZ CENPL-FBP, Fission Barrier Parameter Library; ZZ CENPL-GDRP, Giant Dipole Resonance Parameter Library; ZZ CENPL-NLD, Nuclear Level Density Parameter Library; ZZ CENPL-MCC, Nuclear Ground State Atomic Masses Library; ZZ CENPL-OMP, Optical Model Parameter Library

    International Nuclear Information System (INIS)

    Su Zongdi

    1995-01-01

    Description of program or function: CENPL - GDRP (Giant Dipole Resonance Parameters for Gamma-Ray): - Format: special format described in documentation; - Nuclides: V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Er, Lu, Ta, W, Re, Os, Ir, Pt, Au, Hg, Pb, Bi, Th, U, Np, Pu. - Origin: Experimental values offered by S.S. Dietrich and B.L. Berman. CENPL - FBP (Fission Barrier Parameter Sub-Library): - Format: special format described in documentation; - Nuclides: (1) 51 nuclei region from Th-230 to Cf-255, (2) 46 nuclei region from Th-229 to Cf-253, (3) 24 nuclei region from Pa-232 to Cf-253; - Origin: (1) Lynn, (2) Analysis of experimental data by Back et al., (3) Ohsawa. CENPL - DLS (Discrete level scheme and branch ratio of gamma decay: - Format: Special format described in documentation; - Origin: ENSDF - BNL. CENPL - NLD (Nuclear Level Density): - Format: Special format described in documentation; - Origin: Huang Zhongfu et al. CENPL - OMP (Optical model parameter sub-library): - Format: special format described in documentation ; - Origin: CENDL, ENDF/B-VI, JENDL-3. CENPL - MC (I) and (II) (Atomic masses and characteristic constants for nuclear ground states) : - Format: Brief table format; - Nuclides: 4760 nuclides ranging from Z=0 A=1 to Z=122 A=318. - Origin: Experimental data and systematic results evaluated by Wapstra, theoretical results calculated by Moller, ENSDF - BNL and Nuclear Wallet Cards. CENPL contains the following six sub-libraries: 1. Atomic Masses and Characteristic Constants for nuclear ground states (MCC). This data consists of calculated and in most cases also measured mass excesses, atomic masses, total binding energies, spins, parities, and half-lives of nuclear ground states, abundances, etc. for 4800 nuclides. 2. Discrete Level Schemes and branching ratios of gamma decay (DLS). The data on nuclear discrete levels are based on the Evaluated

  9. Single particle level scheme for alpha decay

    International Nuclear Information System (INIS)

    Mirea, M.

    1998-01-01

    The fine structure phenomenon in alpha decay was evidenced by Rosenblum. In this process the kinetic energy of the emitted particle has several determined values related to the structure of the parent and the daughter nucleus. The probability to find the daughter in a low lying state was considered strongly dependent on the spectroscopic factor defined as the square of overlap between the wave function of the parent in the ground state and the wave functions of the specific excited states of the daughter. This treatment provides a qualitative agreement with the experimental results if the variations of the penetrability between different excited states are neglected. Based on single particle structure during fission, a new formalism explained quantitatively the fine structure of the cluster decay. It was suggested that this formalism can be applied also to alpha decay. For this purpose, the first step is to construct the level scheme of this type of decay. Such a scheme, obtained with the super-asymmetric two-center potential, is plotted for the alpha decay of 223 Ra. It is interesting to note that, diabatically, the level with spin 3/2 emerging from 1i 11/2 (ground state of the parent) reaches an excited state of the daughter in agreement with the experiment. (author)

  10. Nuclear level density

    International Nuclear Information System (INIS)

    Cardoso Junior, J.L.

    1982-10-01

    Experimental data show that the number of nuclear states increases rapidly with increasing excitation energy. The properties of highly excited nuclei are important for many nuclear reactions, mainly those that go via processes of the compound nucleus type. In this case, it is sufficient to know the statistical properties of the nuclear levels. First of them is the function of nuclear levels density. Several theoretical models which describe the level density are presented. The statistical mechanics and a quantum mechanics formalisms as well as semi-empirical results are analysed and discussed. (Author) [pt

  11. Soft rotator model and {sup 246}Cm low-lying level scheme

    Energy Technology Data Exchange (ETDEWEB)

    Porodzinskij, Yu.V.; Sukhovitskij, E.Sh. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    Non-axial soft rotator nuclear model is suggested as self-consistent approach for interpretation of level schemes, {gamma}-transition probabilities and neutron interaction with even-even nuclei. (author)

  12. High level nuclear wastes

    International Nuclear Information System (INIS)

    Lopez Perez, B.

    1987-01-01

    The transformations involved in the nuclear fuels during the burn-up at the power nuclear reactors for burn-up levels of 33.000 MWd/th are considered. Graphs and data on the radioactivity variation with the cooling time and heat power of the irradiated fuel are presented. Likewise, the cycle of the fuel in light water reactors is presented and the alternatives for the nuclear waste management are discussed. A brief description of the management of the spent fuel as a high level nuclear waste is shown, explaining the reprocessing and giving data about the fission products and their radioactivities, which must be considered on the vitrification processes. On the final storage of the nuclear waste into depth geological burials, both alternatives are coincident. The countries supporting the reprocessing are indicated and the Spanish programm defined in the Plan Energetico Nacional (PEN) is shortly reviewed. (author) 8 figs., 4 tabs

  13. Recruitment schemes in new nuclear projects

    International Nuclear Information System (INIS)

    Tielas, M.

    2012-01-01

    Contracting in New Nuclear Projects: A collaborative model between the Owner and the Supplier is described for building nuclear power plants, and is being implemented in the USA as well as in Europe to solve the problem of the risk in the initial investment as experienced in the past: widely exceeded budgets and construction schedules. (Author)

  14. Analysis and design of a nuclear boiler control scheme

    International Nuclear Information System (INIS)

    Hughes, F.M.

    1982-01-01

    The steam raising plant of a British designed nuclear power station for which the installed control scheme has given rise to performance and stability problems is considered. The lecture is based on studies carried out for the plant which illustrate the way in which multivariable frequency response methods can be used to analyse and identify the source of control problems and further enable alternative control schemes, having improved performance, to be designed. (author)

  15. Two-level schemes for the advection equation

    Science.gov (United States)

    Vabishchevich, Petr N.

    2018-06-01

    The advection equation is the basis for mathematical models of continuum mechanics. In the approximate solution of nonstationary problems it is necessary to inherit main properties of the conservatism and monotonicity of the solution. In this paper, the advection equation is written in the symmetric form, where the advection operator is the half-sum of advection operators in conservative (divergent) and non-conservative (characteristic) forms. The advection operator is skew-symmetric. Standard finite element approximations in space are used. The standard explicit two-level scheme for the advection equation is absolutely unstable. New conditionally stable regularized schemes are constructed, on the basis of the general theory of stability (well-posedness) of operator-difference schemes, the stability conditions of the explicit Lax-Wendroff scheme are established. Unconditionally stable and conservative schemes are implicit schemes of the second (Crank-Nicolson scheme) and fourth order. The conditionally stable implicit Lax-Wendroff scheme is constructed. The accuracy of the investigated explicit and implicit two-level schemes for an approximate solution of the advection equation is illustrated by the numerical results of a model two-dimensional problem.

  16. Clarification of nuclear risk recognition scheme through dialogue forum

    International Nuclear Information System (INIS)

    Yagi, Ekou; Takahashi, Makoto; Kitamura, Masaharu

    2007-01-01

    The design framework and operational guidelines for conducting repetitive dialogue between public and nuclear engineers are described in this paper. An action research project named repetitive dialogue forum has been conducted in two municipalities where nuclear facilities were sited. The qualitative evaluation by public participants indicated that the public trust in the nuclear experts, known as the crucial factor for meaningful communication, was successfully established through the dialogue forum. In addition, the expert showed a marked psychological change from distrust to trust in public. Through a detailed analysis of the comments of the participants raised during the forums, the nuclear risk recognition scheme of the public was clarified. The constituents of the risk recognition scheme about nuclear facilities were identified as follows. The first is related to the technical risk recognition factor including purely technical risk, organizational elements and regulatory elements. The second is the social risk recognition factor including economical and mental elements. The last is the communication factor including the influence of mass media, difficulty in frank communication in local community etc. It became clear that the information provision activities conducted by the government and the nuclear industry were lack of in-depth understanding of actual information needs in the public. Provision of information contents consistent with our observations is recommended for reestablishment of public trust in expert and for more informative dialogical interactions. (author)

  17. A new MV bus transfer scheme for nuclear power plants

    International Nuclear Information System (INIS)

    Chang, C.K.

    2015-01-01

    The auxiliary power system of many generating stations consists of offsite power supply system and onsite power supply system, including emergency diesel generators (EDG) to provide secure power to auxiliary loads. If a normal power supply fails to supply power, then the power source is transferred to a standby power supply. In the case of nuclear power plants (NPP), the unit auxiliary transformer (UAT) and standby auxiliary transformer (SAT) - or station service transformer - are installed and powered from 2 offsite power circuits to meet regulatory requirements. The transfer methods of a motor bus from a normal source to a standby source used in power generating stations are fast bus transfer, in-phase transfer, or residual transfer. Fast bus transfer method is the most popular and residual voltage transfer method that is used as a backup in medium voltage buses in general. The use of the advanced technology like open circuit voltage prediction and digital signal processing algorithms can improve the reliability of fast transfer scheme. However, according to the survey results of the recent operation records in nuclear power plants, there were many instances where the fast transfer scheme has failed. To assure bus transfer in any conditions and circumstances, un-interruptible bus transfer scheme utilizing the state of the art medium voltage UPS (Un-interruptible Power Supply) is discussed and elaborated

  18. Revisiting the level scheme of the proton emitter 151Lu

    International Nuclear Information System (INIS)

    Wang, F.; Sun, B.H.; Liu, Z.; Scholey, C.; Eeckhaudt, S.; Grahn, T.; Greenlees, P.T.; Jones, P.; Julin, R.; Juutinen, S.; Kettelhut, S.; Leino, M.; Nyman, M.; Rahkila, P.; Saren, J.; Sorri, J.; Uusitalo, J.; Ashley, S.F.; Cullen, I.J.; Garnsworthy, A.B.; Gelletly, W.; Jones, G.A.; Pietri, S.; Podolyak, Z.; Steer, S.; Thompson, N.J.; Walker, P.M.; Williams, S.; Bianco, L.; Darby, I.G.; Joss, D.T.; Page, R.D.; Pakarinen, J.; Rigby, S.; Cullen, D.M.; Khan, S.; Kishada, A.; Gomez-Hornillos, M.B.; Simpson, J.; Jenkins, D.G.; Niikura, M.; Seweryniak, D.; Shizuma, Toshiyuki

    2015-01-01

    An experiment aiming to search for new isomers in the region of proton emitter 151 Lu was performed at the Accelerator Laboratory of the University of Jyväskylä (JYFL), by combining the high resolution γ-ray array JUROGAM, gas-filled RITU separator and GREAT detectors with the triggerless total data readout acquisition (TDR) system. In this proceeding, we revisit the level scheme of 151 Lu by using the proton-tagging technique. A level scheme consistent with the latest experimental results is obtained, and 3 additional levels are identified at high excitation energies. (author)

  19. Systematics of nuclear level density parameters

    International Nuclear Information System (INIS)

    Bucurescu, Dorel; Egidy, Till von

    2005-01-01

    The level density parameters for the back-shifted Fermi gas (both without and with energy-dependent level density parameter) and the constant temperature models have been determined for 310 nuclei between 18 F and 251 Cf by fitting the complete level schemes at low excitation energies and the s-wave neutron resonance spacings at the neutron binding energies. Simple formulae are proposed for the description of the two parameters of each of these models, which involve only quantities available from the mass tables. These formulae may constitute a reliable tool for extrapolating to nuclei far from stability, where nuclear level densities cannot be measured

  20. Discretisation Schemes for Level Sets of Planar Gaussian Fields

    Science.gov (United States)

    Beliaev, D.; Muirhead, S.

    2018-01-01

    Smooth random Gaussian functions play an important role in mathematical physics, a main example being the random plane wave model conjectured by Berry to give a universal description of high-energy eigenfunctions of the Laplacian on generic compact manifolds. Our work is motivated by questions about the geometry of such random functions, in particular relating to the structure of their nodal and level sets. We study four discretisation schemes that extract information about level sets of planar Gaussian fields. Each scheme recovers information up to a different level of precision, and each requires a maximum mesh-size in order to be valid with high probability. The first two schemes are generalisations and enhancements of similar schemes that have appeared in the literature (Beffara and Gayet in Publ Math IHES, 2017. https://doi.org/10.1007/s10240-017-0093-0; Mischaikow and Wanner in Ann Appl Probab 17:980-1018, 2007); these give complete topological information about the level sets on either a local or global scale. As an application, we improve the results in Beffara and Gayet (2017) on Russo-Seymour-Welsh estimates for the nodal set of positively-correlated planar Gaussian fields. The third and fourth schemes are, to the best of our knowledge, completely new. The third scheme is specific to the nodal set of the random plane wave, and provides global topological information about the nodal set up to `visible ambiguities'. The fourth scheme gives a way to approximate the mean number of excursion domains of planar Gaussian fields.

  1. Shamir secret sharing scheme with dynamic access structure (SSSDAS). Case study on nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Thiyagarajan, P.; Thandra, Prasanth Kumar; Rajan, J.; Satyamurthy, S.A.V. [Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam (India). Computer Div.; Aghila, G. [National Institute of Technology, Karaikal (India). Dept. of Computer Science and Engineering

    2015-05-15

    In recent years, due to the sophistication offered by the Internet, strategic organizations like nuclear power plants are linked to the outside world communication through the Internet. The entry of outside world communication into strategic organization (nuclear power plant) increases the hacker's attempts to crack its security and to trace any information which is being sent among the top level officials. Information security system in nuclear power plant is very crucial as even small loophole in the security system will lead to a major disaster. Recent cyber attacks in nuclear power plant provoked information security professionals to look deeply into the information security aspects of strategic organizations (nuclear power plant). In these lines, Shamir secret sharing scheme with dynamic access structure (SSSDAS) is proposed in the paper which provides enhanced security by providing dynamic access structure for each node in different hierarchies. The SSSDAS algorithm can be applied to any strategic organizations with hierarchical structures. In this paper the possible scenarios where SSSDAS algorithm can be applied to nuclear power plant is explained as a case study. The proposed SSSDAS scheme identifies the wrong shares, if any, used for reconstruction of the secret. The SSSDAS scheme also address the three major security parameters namely confidentiality, authentication and integrity.

  2. Shamir secret sharing scheme with dynamic access structure (SSSDAS). Case study on nuclear power plant

    International Nuclear Information System (INIS)

    Thiyagarajan, P.; Thandra, Prasanth Kumar; Rajan, J.; Satyamurthy, S.A.V.; Aghila, G.

    2015-01-01

    In recent years, due to the sophistication offered by the Internet, strategic organizations like nuclear power plants are linked to the outside world communication through the Internet. The entry of outside world communication into strategic organization (nuclear power plant) increases the hacker's attempts to crack its security and to trace any information which is being sent among the top level officials. Information security system in nuclear power plant is very crucial as even small loophole in the security system will lead to a major disaster. Recent cyber attacks in nuclear power plant provoked information security professionals to look deeply into the information security aspects of strategic organizations (nuclear power plant). In these lines, Shamir secret sharing scheme with dynamic access structure (SSSDAS) is proposed in the paper which provides enhanced security by providing dynamic access structure for each node in different hierarchies. The SSSDAS algorithm can be applied to any strategic organizations with hierarchical structures. In this paper the possible scenarios where SSSDAS algorithm can be applied to nuclear power plant is explained as a case study. The proposed SSSDAS scheme identifies the wrong shares, if any, used for reconstruction of the secret. The SSSDAS scheme also address the three major security parameters namely confidentiality, authentication and integrity.

  3. A novel scheme for making cheap electricity with nuclear energy

    International Nuclear Information System (INIS)

    Pettibone, J.S.

    1991-04-01

    Nuclear fuels should produce cheaper electricity than coal, considering their high specific energy and low cost. To exploit these properties, the scheme proposed here replaces the expensive reactor/steam-turbine system with an engine in which the expansion of a gas heated by a nuclear explosion raises a mass of liquid, thereby producing stored hydraulic energy. This energy could be converted to electricity by hydroelectric generation with water as the working fluid or by magnetohydrodynamic (MHD) generation with molten metal. A rough cost analysis suggests the hydroelectric system could reduce the present cost of electricity by two-thirds, and the MHD system by even more. Such cheap power would make feasible large-scale electrolysis to produce hydrogen and other fuels and chemical raw materials. 2 refs., 1 fig

  4. New data on excited level scheme of 73Ge nucleus

    International Nuclear Information System (INIS)

    Kosyak, Yu.G.; Kaipov, D.K.; Chekushina, L.V.

    1990-01-01

    New data on the scheme of 73 Ge decay obtained by the method of reactor fast neutron inelastic scattering are presented. γ-Spectra from reaction 73 Ge(n, n'γ) 73 Ge at the angles of 90 and 124 deg of relatively incident neutron beam have been measured. Experimental populations of the levels are studied. 29 new γ-transitions have been identified, two new levels have been introduced

  5. Proposed classification scheme for high-level and other radioactive wastes

    International Nuclear Information System (INIS)

    Kocher, D.C.; Croff, A.G.

    1986-01-01

    The Nuclear Waste Policy Act (NWPA) of 1982 defines high-level radioactive waste (HLW) as: (A) the highly radioactive material resulting from the reprocessing of spent nuclear fuel....that contains fission products in sufficient concentrations; and (B) other highly radioactive material that the Commission....determines....requires permanent isolation. This paper presents a generally applicable quantitative definition of HLW that addresses the description in paragraph (B). The approach also results in definitions of other waste classes, i.e., transuranic (TRU) and low-level waste (LLW). A basic waste classification scheme results from the quantitative definitions

  6. Sensor Data Security Level Estimation Scheme for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Alex Ramos

    2015-01-01

    Full Text Available Due to their increasing dissemination, wireless sensor networks (WSNs have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE, a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.

  7. Sensor Data Security Level Estimation Scheme for Wireless Sensor Networks

    Science.gov (United States)

    Ramos, Alex; Filho, Raimir Holanda

    2015-01-01

    Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates. PMID:25608215

  8. Sensor data security level estimation scheme for wireless sensor networks.

    Science.gov (United States)

    Ramos, Alex; Filho, Raimir Holanda

    2015-01-19

    Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.

  9. GRAP, Gamma-Ray Level-Scheme Assignment

    International Nuclear Information System (INIS)

    Franklyn, C.B.

    2002-01-01

    1 - Description of program or function: An interactive program for allocating gamma-rays to an energy level scheme. Procedure allows for searching for new candidate levels of the form: 1) L1 + G(A) + G(B) = L2; 2) G(A) + G(B) = G(C); 3) G(A) + G(B) = C (C is a user defined number); 4) L1 + G(A) + G(B) + G(C) = L2. Procedure indicates intensity balance of feed and decay of each energy level. Provides for optimization of a level energy (and associated error). Overall procedure allows for pre-defining of certain gamma-rays as belonging to particular regions of the level scheme, for example, high energy transition levels, or due to beta- decay. 2 - Method of solution: Search for cases in which the energy difference between two energy levels is equal to a gamma-ray energy within user-defined limits. 3 - Restrictions on the complexity of the problem: Maximum number of gamma-rays: 999; Maximum gamma ray energy: 32000 units; Minimum gamma ray energy: 10 units; Maximum gamma-ray intensity: 32000 units; Minimum gamma-ray intensity: 0.001 units; Maximum number of levels: 255; Maximum level energy: 32000 units; Minimum level energy: 10 units; Maximum error on energy, intensity: 32 units; Minimum error on energy, intensity: 0.001 units; Maximum number of combinations: 6400 (ca); Maximum number of gamma-ray types : 127

  10. Combinatorial nuclear level-density model

    International Nuclear Information System (INIS)

    Uhrenholt, H.; Åberg, S.; Dobrowolski, A.; Døssing, Th.; Ichikawa, T.; Möller, P.

    2013-01-01

    A microscopic nuclear level-density model is presented. The model is a completely combinatorial (micro-canonical) model based on the folded-Yukawa single-particle potential and includes explicit treatment of pairing, rotational and vibrational states. The microscopic character of all states enables extraction of level-distribution functions with respect to pairing gaps, parity and angular momentum. The results of the model are compared to available experimental data: level spacings at neutron separation energy, data on total level-density functions from the Oslo method, cumulative level densities from low-lying discrete states, and data on parity ratios. Spherical and deformed nuclei follow basically different coupling schemes, and we focus on deformed nuclei

  11. Nuclear power: levels of safety

    International Nuclear Information System (INIS)

    Lidsky, L.M.

    1988-01-01

    The rise and fall of the nuclear power industry in the United States is a well-documented story with enough socio-technological conflict to fill dozens of scholarly, and not so scholarly, books. Whatever the reasons for the situation we are now in, and no matter how we apportion the blame, the ultimate choice of whether to use nuclear power in this country is made by the utilities and by the public. Their choices are, finally, based on some form of risk-benefit analysis. Such analysis is done in well-documented and apparently logical form by the utilities and in a rather more inchoate but not necessarily less accurate form by the public. Nuclear power has failed in the United States because both the real and perceived risks outweigh the potential benefits. The national decision not to rely upon nuclear power in its present form is not an irrational one. A wide ranging public balancing of risk and benefit requires a classification of risk which is clear and believable for the public to be able to assess the risks associated with given technological structures. The qualitative four-level safety ladder provides such a framework. Nuclear reactors have been designed which fit clearly and demonstrably into each of the possible qualitative safety levels. Surprisingly, it appears that safer may also mean cheaper. The intellectual and technical prerequisites are in hand for an important national decision. Deployment of a qualitatively different second generation of nuclear reactors can have important benefits for the United States. Surprisingly, it may well be the nuclear establishment itself, with enormous investments of money and pride in the existing nuclear systems, that rejects second generation reactors. It may be that we will not have a second generation of reactors until the first generation of nuclear engineers and nuclear power advocates has retired

  12. Discrete level schemes sublibrary. Progress report by Budapest group

    International Nuclear Information System (INIS)

    Oestor, J.; Belgya, T.; Molnar, G.L.

    1997-01-01

    An entirely new discrete levels file has been created by the Budapest group according to the recommended principles, using the Evaluated Nuclear Structure Data File, ENSDF as a source. The resulting library contains 96,834 levels and 105,423 gamma rays for 2,585 nuclei, with their characteristics such as energy, spin, parity, half-life as well gamma-ray energy and branching percentage

  13. The nuclear heating calculation scheme for material testing in the future Jules Horowitz Reactor

    International Nuclear Information System (INIS)

    Huot, N.; Aggery, A.; Blanchet, D.; Courcelle, A.; Czernecki, S.; Di-Salvo, J.; Doederlein, C.; Serviere, H.; Willermoz, G.

    2004-01-01

    An innovative nuclear heating calculation scheme for materials testing carried out in in the future Jules Horowitz reactor (JHR) is described. A heterogeneous gamma source calculation is first performed at assembly level using the deterministic code APOLLO2. This is followed by a Monte Carlo gamma transport calculation in the whole core using the TRIPOLI4 code. The calculated gamma sources at the assembly level are applied in the whole core simulation using a weighting based on power distribution obtained from the neutronic core calculation. (authors)

  14. Adopting the EU sustainable performance scheme Level(s) in the Danish building sector

    DEFF Research Database (Denmark)

    Kanafani, Kai; Rasmussen, Freja Nygaard; Zimmermann, Regitze Kjær

    2018-01-01

    to life cycle assessment (LCA) requirements within the Level(s) scheme. As a measure for the Danish building sector’s LCA practice, the specifications for LCAbyg, the official Danish building LCA tool, is used. In 2017, the European commission’s Joint Research Centre has launched Level(s) as a vo...

  15. Nuclear systems of level measurement

    International Nuclear Information System (INIS)

    Lara, A.J.; Cabrera, M.J.

    1992-01-01

    In the industry there are processes in which is necessary to maintain the products level controlled which are handled for their transformation. The majority of such processes and by the operation conditions, they do not admit measure systems of level of invasive type then the application of nuclear techniques for level measurement results a big aid in these cases, since all the system installation is situated beyond frontiers of vessels that contain the product for measuring. In the Department of Nuclear Technology Applications of Mexican Petroleum Institute was developed a level measurement system by gamma rays transmission which operates in the Low Density Polyethylene plant of Petrochemical Complex Escolin at Poza Rica, Veracruz, Mexico. (Author)

  16. Histogram plots and cutoff energies for nuclear discrete levels

    International Nuclear Information System (INIS)

    Belgya, T.; Molnar, G.; Fazekas, B.; Oestoer, J.

    1997-05-01

    Discrete level schemes for 1277 nuclei, from 6 Li through 251 Es, extracted from the Evaluated Nuclear Structure Data File were analyzed. Cutoff energies (U max ), indicating the upper limit of level scheme completeness, were deduced from the inspection of histograms of the cumulative number of levels. Parameters of the constant-temperature level density formula (nuclear temperature T and energy shift U 0 ) were obtained by means of the least square fit of the formula to the known levels below cutoff energy. The results are tabulated for all 1277 nuclei allowing for an easy and reliable application of the constant-temperature level density approach. A complete set of cumulative plots of discrete levels is also provided. (author). 5 figs, 2 tabs

  17. Funding schemes in OECD countries for future decommissioning of nuclear power

    International Nuclear Information System (INIS)

    Stevens, G.H.; Yasui, M.

    1993-01-01

    This paper provides a brief overview of the funding schemes for decommissioning implemented in selected OECD countries. The scope of this paper includes only the schemes for future decommissioning costs of private company's nuclear power plants. Countries such as Finland, Spain and Sweden have an official funding scheme, in which the government fixes the amount of money to be put aside, specifies a funding scheme and control the fund. In Belgium and Usa, the government do the same but leaves the management of the fund to the facility owners or external organization. In Canada, France, Germany, Italy, Japan, Netherlands and UK, there is no official funding scheme

  18. Proposed classification scheme for high-level and other radioactive wastes

    International Nuclear Information System (INIS)

    Kocher, D.C.; Croff, A.G.

    1986-01-01

    The Nuclear Waste Policy Act (NWPA) of 1982 defines high-level (radioactive) waste (HLW) as (A) the highly radioactive material resulting from the reprocessing of spent nuclear fuel...that contains fission products in sufficient concentrations; and (B) other highly radioactive material that the Commission...determines...requires permanent isolation. This paper presents a generally applicable quantitative definition of HLW that addresses the description in paragraph B. The approach also results in definitions of other wastes classes, i.e., transuranic (TRU) and low-level waste (LLW). The basic waste classification scheme that results from the quantitative definitions of highly radioactive and requires permanent isolation is depicted. The concentrations of radionuclides that correspond to these two boundaries, and that may be used to classify radioactive wastes, are given

  19. Nuclear analytical chemistry 5. Tables, nomograms and schemes

    Energy Technology Data Exchange (ETDEWEB)

    Tolgyessy, J; Varga, S; Dillinger, P; Kyrs, M

    1976-01-01

    Tables, graphs and nomograms are given on aspects of nuclear analytical chemistry. The tables contain data on physical and chemical units and their conversion, exponential functions, the characteristics of radioactive nuclides, data on the interaction of nuclear radiation with matter, data useful in measuring nuclear radiation, in scintillation and semiconductor spectrometry, activation analysis, data on masking reactions of ions in chemical separation, on extraction, ion exchange, accuracy in applying the method of isotope dilution, on radiochemical analysis.

  20. Pixel detector readout electronics with two-level discriminator scheme

    International Nuclear Information System (INIS)

    Pengg, F.

    1998-01-01

    In preparation for a silicon pixel detector with more than 3,000 readout channels per chip for operation at the future large hadron collider (LHC) at CERN the analog front end of the readout electronics has been designed and measured on several test-arrays with 16 by 4 cells. They are implemented in the HP 0.8 microm process but compatible with the design rules of the radiation hard Honeywell 0.8 microm bulk process. Each cell contains bump bonding pad, preamplifier, discriminator and control logic for masking and testing within a layout area of only 50 microm by 140 microm. A new two-level discriminator scheme has been implemented to cope with the problems of time-walk and interpixel cross-coupling. The measured gain of the preamplifier is 900 mV for a minimum ionizing particle (MIP, about 24,000 e - for a 300 microm thick Si-detector) with a return to baseline within 750 ns for a 1 MIP input signal. The full readout chain (without detector) shows an equivalent noise charge to 60e - r.m.s. The time-walk, a function of the separation between the two threshold levels, is measured to be 22 ns at a separation of 1,500 e - , which is adequate for the 40 MHz beam-crossing frequency at the LHC. The interpixel cross-coupling, measured with a 40fF coupling capacitance, is less than 3%. A single cell consumes 35 microW at 3.5 V supply voltage

  1. Application of stable adaptive schemes to nuclear reactor systems, (1)

    International Nuclear Information System (INIS)

    Fukuda, Toshio

    1978-01-01

    Parameter identification and adaptive control schemes are presented for a point reactor with internal feedbacks which lead to the nonlinearity of the overall system. Both are shown stable with new representation of the system, which corresponds to the nonminimal system representation, in the vein of the Model Reference Adaptive System (MRAS) via the Lyapunov's method. For the sake of the parameter identification, model parameters can be adjusted adaptively as soon as measurements start, while plant parameters can also adaptively be compensated through control input to reduce the output error between the model and the plant for the case of the adaptive control. In the case of the adaptive control, control schemes are presented for two cases, the case of the unknown decay constant of the delayed neutron and the case of the known constant. The adaptive control scheme for the latter case is shown extremely simpler than that for the former. Furthermore, when plant parameters vary slowly with time, computer simulations show that the proposed adaptive control scheme works satisfactorily enough to stabilize an unstable reactor and that it does even in the noise with small variance. (auth.)

  2. Nuclear Reactor Component Code CUPID-I: Numerical Scheme and Preliminary Assessment Results

    International Nuclear Information System (INIS)

    Cho, Hyoung Kyu; Jeong, Jae Jun; Park, Ik Kyu; Kim, Jong Tae; Yoon, Han Young

    2007-12-01

    A component scale thermal hydraulic analysis code, CUPID (Component Unstructured Program for Interfacial Dynamics), is being developed for the analysis of components of a nuclear reactor, such as reactor vessel, steam generator, containment, etc. It adopted three-dimensional, transient, two phase and three-field model. In order to develop the numerical schemes for the three-field model, various numerical schemes have been examined including the SMAC, semi-implicit ICE, SIMPLE, Row Scheme and so on. Among them, the ICE scheme for the three-field model was presented in the present report. The CUPID code is utilizing unstructured mesh for the simulation of complicated geometries of the nuclear reactor components. The conventional ICE scheme that was applied to RELAP5 and COBRA-TF, therefore, were modified for the application to the unstructured mesh. Preliminary calculations for the unstructured semi-implicit ICE scheme have been conducted for a verification of the numerical method from a qualitative point of view. The preliminary calculation results showed that the present numerical scheme is robust and efficient for the prediction of phase changes and flow transitions due to a boiling and a flashing. These calculation results also showed the strong coupling between the pressure and void fraction changes. Thus, it is believed that the semi-implicit ICE scheme can be utilized for transient two-phase flows in a component of a nuclear reactor

  3. Nuclear Reactor Component Code CUPID-I: Numerical Scheme and Preliminary Assessment Results

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyoung Kyu; Jeong, Jae Jun; Park, Ik Kyu; Kim, Jong Tae; Yoon, Han Young

    2007-12-15

    A component scale thermal hydraulic analysis code, CUPID (Component Unstructured Program for Interfacial Dynamics), is being developed for the analysis of components of a nuclear reactor, such as reactor vessel, steam generator, containment, etc. It adopted three-dimensional, transient, two phase and three-field model. In order to develop the numerical schemes for the three-field model, various numerical schemes have been examined including the SMAC, semi-implicit ICE, SIMPLE, Row Scheme and so on. Among them, the ICE scheme for the three-field model was presented in the present report. The CUPID code is utilizing unstructured mesh for the simulation of complicated geometries of the nuclear reactor components. The conventional ICE scheme that was applied to RELAP5 and COBRA-TF, therefore, were modified for the application to the unstructured mesh. Preliminary calculations for the unstructured semi-implicit ICE scheme have been conducted for a verification of the numerical method from a qualitative point of view. The preliminary calculation results showed that the present numerical scheme is robust and efficient for the prediction of phase changes and flow transitions due to a boiling and a flashing. These calculation results also showed the strong coupling between the pressure and void fraction changes. Thus, it is believed that the semi-implicit ICE scheme can be utilized for transient two-phase flows in a component of a nuclear reactor.

  4. Schemes for Probabilistic Teleportation of an Unknown Three-Particle Three-Level Entangled State

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, two schemes for teleporting an unknown three-particle three-level entangled state are proposed. In the first scheme, two partial three-particle three-level entangled states are used as the quantum channels, while in the second scheme, three two-particle three-level non-maximally entangled states are employed as quantum channels.It is shown that the teleportation can be successfully realized with certain probability, for both two schemes, if a receiver adopts some appropriate unitary transformations. It is shown also that the successful probabilities of these two schemes are different.

  5. Signature scheme for the microscopic description of nuclear collective excitations

    International Nuclear Information System (INIS)

    Ogawa, K.

    1980-04-01

    The symmetries between the proton and neutron systems in a nucleus are described in terms of the signatures. Three kinds of signatures (i.e. the pn-, p anti n- and p anti p- (or n anti n-) signatures) are introduced and they are related to the appearance of various collective motions such as rotations or vibrations. It is shown that the pn-signature scheme provides a band-like structure of deformed nuclei, while the features associated with the quadrupole vibration are obtained in the p anti n- and p anti p-signature scheme. From the detail investigation of the p anti n-symmetric wave functions, it is concluded that the reguralities provided by the present shell model are more analogous to those of the γ-unstable surface vibration model (Wilets-Jean model) than to those of harmonic phonon model. (author)

  6. Energy mesh optimization for multi-level calculation schemes

    International Nuclear Information System (INIS)

    Mosca, P.; Taofiki, A.; Bellier, P.; Prevost, A.

    2011-01-01

    The industrial calculations of third generation nuclear reactors are based on sophisticated strategies of homogenization and collapsing at different spatial and energetic levels. An important issue to ensure the quality of these calculation models is the choice of the collapsing energy mesh. In this work, we show a new approach to generate optimized energy meshes starting from the SHEM 281-group library. The optimization model is applied on 1D cylindrical cells and consists of finding an energy mesh which minimizes the errors between two successive collision probability calculations. The former is realized over the fine SHEM mesh with Livolant-Jeanpierre self-shielded cross sections and the latter is performed with collapsed cross sections over the energy mesh being optimized. The optimization is done by the particle swarm algorithm implemented in the code AEMC and multigroup flux solutions are obtained from standard APOLLO2 solvers. By this new approach, a set of new optimized meshes which encompass from 10 to 50 groups has been defined for PWR and BWR calculations. This set will allow users to adapt the energy detail of the solution to the complexity of the calculation (assembly, multi-assembly, two-dimensional whole core). Some preliminary verifications, in which the accuracy of the new meshes is measured compared to a direct 281-group calculation, show that the 30-group optimized mesh offers a good compromise between simulation time and accuracy for a standard 17 x 17 UO 2 assembly with and without control rods. (author)

  7. Thermodynamics of excited nuclei and nuclear level densities

    International Nuclear Information System (INIS)

    Ramamurthy, V.S.

    1977-01-01

    A review has been made of the different approaches that are being used for a theoretical calculation of nuclear level densities. It is pointed out that while the numerical calculations based on the partition function approach and shell model single particle level schemes have shed important insight into the influence of nuclear shell effects on level densities and its excitation energy dependence and have brought out the inadequacy of the conventional Bethe Formula, these calculations are yet to reach a level where they can be directly used for quantitative comparisons. Some of the important drawbacks of the numerical calculations are also discussed. In this context, a new semi-empirical level density formula is described which while retaining the simplicity of analytical formulae, takes into account nuclear shell effects in a more realistic manner. (author)

  8. Application of stable adaptive schemes to nuclear reactor systems, (2)

    International Nuclear Information System (INIS)

    Kukuda, Toshio

    1979-01-01

    The parameter identification and adaptive control schemes applied in a previous study to a nonlinear point reactor are extended to the case of a loosely-coupled-core reactor with internal feedbacks, constituting a nonlinear overall system. Both schemes are shown to be stable, with the system newly represented on the pattern of the Model Reference Adaptive System (MRAS) with use made of the Lyapunov's method. For either parameter identification or adaptive control of a loosely-coupled-core reactor, there exists no canonical form of multiple input-multiple output system which can be directly applied for deriving the MRAS with the matrix version of the Kalman-Yakubovich lemma as it was in the case of the point reactor. This difficulty is circumvented by the practical assumption that the neutron density can be directly measured on each core as reactivity change is applied as input into the coupled core as a whole. For parameter identification, the model parameters are adaptively adjusted to those of each core, while for the adaptive control, plant parameters of each core can be adaptively compensated, again through control inputs, to asymptotically reduce the output error between the model and the plant. The point reactor is shown to correspond to a special case. (author)

  9. Development of Cyber Security Scheme for Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hong, S. B.; Choi, Y. S.; Cho, J. W. (and others)

    2009-12-15

    Nuclear I and C system is considered to be safe on the cyber threat because of the use of exclusive communication network and operating system. But the trend of open architecture and standardization on the equipment of I and C system, it is not safe on the cyber threat such as hacking and cyber terror. It is needed to protect nuclear I and C systems by the cyber attack, Countermeasures of the cyber security is required a lot of time and endeavors because there are many factors on the environment of cyber security and cyber attack. For the nuclear cyber security, we should make structural framework and eliminate cyber vulnerabilities by the analysis of cyber environment. The framework for the cyber security includes planning, embodiment of security technologies, security audit, security management and security maintenance. In this report, we examined IT security technology and the trend of standard in the industrial I and C system, and proposed a method to construct cyber security for the nuclear power plant. We analysed the threat of cyber security, vulnerability and cyber risk, then we present a method for the cyber security structure and the countermeasures.

  10. Development of Cyber Security Scheme for Nuclear Power Plant

    International Nuclear Information System (INIS)

    Hong, S. B.; Choi, Y. S.; Cho, J. W.

    2009-12-01

    Nuclear I and C system is considered to be safe on the cyber threat because of the use of exclusive communication network and operating system. But the trend of open architecture and standardization on the equipment of I and C system, it is not safe on the cyber threat such as hacking and cyber terror. It is needed to protect nuclear I and C systems by the cyber attack, Countermeasures of the cyber security is required a lot of time and endeavors because there are many factors on the environment of cyber security and cyber attack. For the nuclear cyber security, we should make structural framework and eliminate cyber vulnerabilities by the analysis of cyber environment. The framework for the cyber security includes planning, embodiment of security technologies, security audit, security management and security maintenance. In this report, we examined IT security technology and the trend of standard in the industrial I and C system, and proposed a method to construct cyber security for the nuclear power plant. We analysed the threat of cyber security, vulnerability and cyber risk, then we present a method for the cyber security structure and the countermeasures

  11. Chemical Plant Accidents in a Nuclear Hydrogen Generation Scheme

    International Nuclear Information System (INIS)

    Brown, Nicholas R.; Revankar, Shripad T.

    2011-01-01

    A high temperature nuclear reactor (HTR) could be used to drive a steam reformation plant, a coal gasification facility, an electrolysis plant, or a thermochemical hydrogen production cycle. Most thermochemical cycles are purely thermodynamic, and thus achieve high thermodynamic efficiency. HTRs produce large amounts of heat at high temperature (1100 K). Helium-cooled HTRs have many passive, or inherent, safety characteristics. This inherent safety is due to the high design basis limit of the maximum fuel temperature. Due to the severity of a potential release, containment of fission products is the single most important safety issue in any nuclear reactor facility. A HTR coupled to a chemical plant presents a complex system, due primarily to the interactive nature of both plants. Since the chemical plant acts as the heat sink for the nuclear reactor, it important to understand the interaction and feedback between the two systems. Process heat plants and HTRs are generally very different. Some of the major differences include: time constants of plants, safety standards, failure probability, and transient response. While both the chemical plant and the HTR are at advanced stages of testing individually, no serious effort has been made to understand the operation of the integrated system, especially during accident events that are initiated in the chemical plant. There is a significant lack of knowledge base regarding scaling and system integration for large scale process heat plants coupled to HTRs. Consideration of feedback between the two plants during time-dependent scenarios is absent from literature. Additionally, no conceptual studies of the accidents that could occur in either plant and impact the entire coupled system are present in literature

  12. Advanced scheme for high-yield laser driven nuclear reactions

    Czech Academy of Sciences Publication Activity Database

    Margarone, Daniele; Picciotto, A.; Velyhan, Andriy; Krása, Josef; Kucharik, M.; Mangione, A.; Szydlowsky, A.; Malinowska, A.; Bertuccio, G.; Shi, Y.; Crivellari, M.; Ullschmied, Jiří; Bellutti, P.; Korn, Georg

    2015-01-01

    Roč. 57, č. 1 (2015), s. 014030 ISSN 0741-3335 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk EE2.3.20.0279 EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; LaserZdroj (OP VK 3)(XE) CZ.1.07/2.3.00/20.0279 Institutional research plan: CEZ:AV0Z2043910 Institutional support: RVO:68378271 ; RVO:61389021 Keywords : laser plasma * nuclear reaction * laser fusion Subject RIV: BL - Plasma and Gas Discharge Physics; BH - Optics, Masers, Lasers (UFP-V) Impact factor: 2.404, year: 2015

  13. Performance of a Two-Level Call Admission Control Scheme for DS-CDMA Wireless Networks

    Directory of Open Access Journals (Sweden)

    Fapojuwo Abraham O

    2007-01-01

    Full Text Available We propose a two-level call admission control (CAC scheme for direct sequence code division multiple access (DS-CDMA wireless networks supporting multimedia traffic and evaluate its performance. The first-level admission control assigns higher priority to real-time calls (also referred to as class 0 calls in gaining access to the system resources. The second level admits nonreal-time calls (or class 1 calls based on the resources remaining after meeting the resource needs for real-time calls. However, to ensure some minimum level of performance for nonreal-time calls, the scheme reserves some resources for such calls. The proposed two-level CAC scheme utilizes the delay-tolerant characteristic of non-real-time calls by incorporating a queue to temporarily store those that cannot be assigned resources at the time of initial access. We analyze and evaluate the call blocking, outage probability, throughput, and average queuing delay performance of the proposed two-level CAC scheme using Markov chain theory. The analytic results are validated by simulation results. The numerical results show that the proposed two-level CAC scheme provides better performance than the single-level CAC scheme. Based on these results, it is concluded that the proposed two-level CAC scheme serves as a good solution for supporting multimedia applications in DS-CDMA wireless communication systems.

  14. Performance of a Two-Level Call Admission Control Scheme for DS-CDMA Wireless Networks

    Directory of Open Access Journals (Sweden)

    Abraham O. Fapojuwo

    2007-11-01

    Full Text Available We propose a two-level call admission control (CAC scheme for direct sequence code division multiple access (DS-CDMA wireless networks supporting multimedia traffic and evaluate its performance. The first-level admission control assigns higher priority to real-time calls (also referred to as class 0 calls in gaining access to the system resources. The second level admits nonreal-time calls (or class 1 calls based on the resources remaining after meeting the resource needs for real-time calls. However, to ensure some minimum level of performance for nonreal-time calls, the scheme reserves some resources for such calls. The proposed two-level CAC scheme utilizes the delay-tolerant characteristic of non-real-time calls by incorporating a queue to temporarily store those that cannot be assigned resources at the time of initial access. We analyze and evaluate the call blocking, outage probability, throughput, and average queuing delay performance of the proposed two-level CAC scheme using Markov chain theory. The analytic results are validated by simulation results. The numerical results show that the proposed two-level CAC scheme provides better performance than the single-level CAC scheme. Based on these results, it is concluded that the proposed two-level CAC scheme serves as a good solution for supporting multimedia applications in DS-CDMA wireless communication systems.

  15. Analysis of floor technology scheme in open-top construction of nuclear power project

    International Nuclear Information System (INIS)

    Zhang Shuxia; Lu Qinwu; Han Xiaoping

    2014-01-01

    Open-top construction is general technology in Ⅲ generation in nuclear power project. Because traditional floor structure and its form board upholding doesn't meet open-top construction, four floor scheme are presented, whose characters, advantages and disadvantages, and its application are summarized. The research results will help to the application of open-top construction. (authors)

  16. Four-level conservative finite-difference schemes for Boussinesq paradigm equation

    Science.gov (United States)

    Kolkovska, N.

    2013-10-01

    In this paper a two-parametric family of four level conservative finite difference schemes is constructed for the multidimensional Boussinesq paradigm equation. The schemes are explicit in the sense that no inner iterations are needed for evaluation of the numerical solution. The preservation of the discrete energy with this method is proved. The schemes have been numerically tested on one soliton propagation model and two solitons interaction model. The numerical experiments demonstrate that the proposed family of schemes has second order of convergence in space and time steps in the discrete maximal norm.

  17. A scheme for the audit of scientific and technological standards in clinical nuclear medicine

    International Nuclear Information System (INIS)

    Perkins, A.C.; Jarritt, P.H.

    2002-01-01

    Aim: Audit is the process whereby the quality of a service is monitored and optimised. It forms an essential component of the quality assurance process, whether by self-assessment or by external peer review. In the UK the British Nuclear Medicine Society (BNMS) has undertaken external organisational audit of departments providing clinical nuclear medicine services. This work aimed to develop a more thorough and service specific process for the audit of scientific and technological standards in nuclear medicine. Materials and Methods: The audit process has been implemented using written audit documents to facilitate the audit procedure. A questionnaire forms part of the formal documentation for audit of the scientific and technical standards of a clinical service. Scientific and technical standards were derived from a number of sources including legal requirements, regulatory obligations, notes for guidance, peer reviewed publications and accepted good clinical practice (GCP). Results: The audit process graded the standards of an individual department according to legal or safety requirements (Grade A), good practice (Grade B) and desirable aspects of service delivery (Grade C). The standards have been allocated into eight main categories. These are: Instrumentation; Software and data protection; Electrical Safety; Mechanical Safety; Workstation Safety; The Control of Substances Hazardous to Health (COSHH); Radiation Protection; Scientific and Technical staffing levels. During the audit visit a detailed inspection of clinical and laboratory areas and department written documentation is also necessary to validate the data obtained. Conclusion: The printed scheme now provides a means for external audit or self-assessment. There should be evidence of a well-organised and safe environment for both patients and staff. Health and Safety legislation requires written local rules and these records should be available to demonstrate the standard of service provision. Other

  18. Level density from realistic nuclear potentials

    International Nuclear Information System (INIS)

    Calboreanu, A.

    2006-01-01

    Nuclear level density of some nuclei is calculated using a realistic set of single particle states (sps). These states are derived from the parameterization of nuclear potentials that describe the observed sps over a large number of nuclei. This approach has the advantage that one can infer level density for nuclei that are inaccessible for a direct study, but are very important in astrophysical processes such as those close to the drip lines. Level densities at high excitation energies are very sensitive to the actual set of sps. The fact that the sps spectrum is finite has extraordinary consequences upon nuclear reaction yields due to the leveling-off of the level density at extremely high excitation energies wrongly attributed so far to other nuclear effects. Single-particle level density parameter a parameter is extracted by fitting the calculated densities to the standard Bethe formula

  19. Evaluation of beta intensity data in nuclear decay schemes: Comments on some pitfalls

    International Nuclear Information System (INIS)

    Reich, C.W.

    1987-02-01

    Some of the problems that arise in the evaluation of decay-schemes data to obtain values for the intensities of beta transitions are discussed. As examples of these problems, the decay schemes of 87 Br and 233 Pa are examined. No specific solutions to these problems are offered; but by pointing out to the participants in the International Nuclear Structure and Decay Data Evaluation Network, and to others, it is hoped that a general understanding of them can be gained, which may ultimately lead to a consistent means of dealing with them. 14 refs., 2 figs

  20. Evaluation of β intensity data in nuclear decay schemes: comments on some pitfalls

    International Nuclear Information System (INIS)

    Reich, C.W.

    1986-01-01

    Some of the problems which arise in the evaluation of decay-schemes data to obtain values for the intensities of β transitions are discussed. As examples of these problems, the decay schemes of 87 Br and 233 Pa are examined. No specific solutions to these problems are offered; but by pointing them out to the participants in the International Nuclear Structure and Decay Data Evaluation Network, it is hoped that a general understanding of them can be gained, which may ultimately lead to a consistent means of dealing with them. 14 refs., 2 figs., 1 tab

  1. Combinatorial nuclear level density by a Monte Carlo method

    International Nuclear Information System (INIS)

    Cerf, N.

    1994-01-01

    We present a new combinatorial method for the calculation of the nuclear level density. It is based on a Monte Carlo technique, in order to avoid a direct counting procedure which is generally impracticable for high-A nuclei. The Monte Carlo simulation, making use of the Metropolis sampling scheme, allows a computationally fast estimate of the level density for many fermion systems in large shell model spaces. We emphasize the advantages of this Monte Carlo approach, particularly concerning the prediction of the spin and parity distributions of the excited states,and compare our results with those derived from a traditional combinatorial or a statistical method. Such a Monte Carlo technique seems very promising to determine accurate level densities in a large energy range for nuclear reaction calculations

  2. Schemes of detecting nuclear spin correlations by dynamical decoupling based quantum sensing

    Science.gov (United States)

    Ma, Wen-Long Ma; Liu, Ren-Bao

    Single-molecule sensitivity of nuclear magnetic resonance (NMR) and angstrom resolution of magnetic resonance imaging (MRI) are the highest challenges in magnetic microscopy. Recent development in dynamical decoupling (DD) enhanced diamond quantum sensing has enabled NMR of single nuclear spins and nanoscale NMR. Similar to conventional NMR and MRI, current DD-based quantum sensing utilizes the frequency fingerprints of target nuclear spins. Such schemes, however, cannot resolve different nuclear spins that have the same noise frequency or differentiate different types of correlations in nuclear spin clusters. Here we show that the first limitation can be overcome by using wavefunction fingerprints of target nuclear spins, which is much more sensitive than the ''frequency fingerprints'' to weak hyperfine interaction between the targets and a sensor, while the second one can be overcome by a new design of two-dimensional DD sequences composed of two sets of periodic DD sequences with different periods, which can be independently set to match two different transition frequencies. Our schemes not only offer an approach to breaking the resolution limit set by ''frequency gradients'' in conventional MRI, but also provide a standard approach to correlation spectroscopy for single-molecule NMR.

  3. Role of proper response schemes, legislation and regional cooperation in combating illicit trafficking of nuclear materials in developing countries

    International Nuclear Information System (INIS)

    Sterzov, A.

    2002-01-01

    Full text: The suitable geographical situation on the crossroad between Europe, the former Soviet Union and the Middle East puts Bulgaria into the stream of many illegal traffics - people, arms, drugs etc. The illicit traffic of nuclear and radioactive materials is a serious violation of nonproliferation laws as well as a risk for the health of the population. Criminal diversion of fissile materials could lead to the potential construction of nuclear weapon or applied with conventional explosives the radioactive material could pose a threat to dwelling places, water supplies etc. The traffic of nuclear and radioactive materials in Bulgaria can be divided in two main parts -- internal and transit. I. Internal traffic The internal traffic consisted of stolen radioactive sources mainly imported with the Soviet equipment from companies or plants that were privatized or stopped functioning due to the economic changes in the country. There there were attempts to divert and transport materials from the Uranium mining industry including different amounts of 'yellow cake', depleted Uranium containers or shielding. These devices consisted of level and dense meters, irradiation devices, removing static electricity, smoke detectors etc. mainly containing the isotopes Cs-137, Co-60, Ir-192, Ra-226, Am-241 etc. II. External traffic The external traffic of illicit nuclear materials is connected with the transfer of raw materials and expensive metals from the former Soviet Union towards Western Europe and the Middle East. This traffic included Al, Os, Cs, Sc, Rare earth elements, Red Mercury, Pu, Enriched U. The traffic of the last three items is of greatest concern and should be addressed with highest priority. III. Response to the illicit traffic of nuclear materials The detection of both the internal and external traffic raises serious problems to the Bulgarian controlling organs both for equipment and qualified personnel at the borders and inside the country. The creation of

  4. Scheme of 2-dimensional atom localization for a three-level atom via quantum coherence

    OpenAIRE

    Zafar, Sajjad; Ahmed, Rizwan; Khan, M. Khalid

    2013-01-01

    We present a scheme for two-dimensional (2D) atom localization in a three-level atomic system. The scheme is based on quantum coherence via classical standing wave fields between the two excited levels. Our results show that conditional position probability is significantly phase dependent of the applied field and frequency detuning of spontaneously emitted photons. We obtain a single localization peak having probability close to unity by manipulating the control parameters. The effect of ato...

  5. ESCL8R and LEVIT8R: interactive graphical analysis of {gamma}-{gamma} and {gamma}-{gamma}-{gamma} coincidence data for level schemes

    Energy Technology Data Exchange (ETDEWEB)

    Radford, D C [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.

    1992-08-01

    The extraction of complete and consistent nuclear level schemes from high-fold coincidence data will require intelligent computer programs. These will need to present the relevant data in an easily assimilated manner, keep track of all {gamma}-ray assignments and expected coincidence intensities, and quickly find significant discrepancies between a proposed level scheme and the data. Some steps in this direction have been made at Chalk River. The programs ESCL8R and LEVIT8R, for analysis of two-fold and three-fold data sets respectively, allow fast and easy inspection of the data, and compare the results to expectations calculations on the basis of a proposed level scheme. Least-squares fits directly to the 2D and/or 3D data, with the intensities and energies of the level scheme transitions as parameters, allow fast and easy extraction of the optimum physics results. (author). 4 refs., 3 figs.

  6. A scheme for the evaluation of dominant time-eigenvalues of a nuclear reactor

    International Nuclear Information System (INIS)

    Modak, R.S.; Gupta, Anurag

    2007-01-01

    This paper presents a scheme to obtain the fundamental and few dominant solutions of the prompt time eigenvalue problem (referred to as α-eigenvalue problem) for a nuclear reactor using multi-group neutron diffusion theory. The scheme is based on the use of an algorithm called Orthomin(1). This algorithm was originally proposed by Suetomi and Sekimoto [Suetomi, E., Sekimoto, H., 1991. Conjugate gradient like methods and their application to eigenvalue problems for neutron diffusion equations. Ann. Nucl. Energy 18 (4), 205-227] to obtain the fundamental K-eigenvalue (K-effective) of nuclear reactors. Recently, it has been shown that the algorithm can be used to obtain the further dominant K-modes also. Since α-eigenvalue problem is usually more difficult to solve than the K-eigenvalue problem, an attempt has been made here to use Orthomin(1) for its solution. Numerical results are given for realistic 3-D test case

  7. Level densities in nuclear physics

    International Nuclear Information System (INIS)

    Beckerman, M.

    1978-01-01

    In the independent-particle model nucleons move independently in a central potential. There is a well-defined set of single- particle orbitals, each nucleon occupies one of these orbitals subject to Fermi statistics, and the total energy of the nucleus is equal to the sum of the energies of the individual nucleons. The basic question is the range of validity of this Fermi gas description and, in particular, the roles of the residual interactions and collective modes. A detailed examination of experimental level densities in light-mass system is given to provide some insight into these questions. Level densities over the first 10 MeV or so in excitation energy as deduced from neutron and proton resonances data and from spectra of low-lying bound levels are discussed. To exhibit some of the salient features of these data comparisons to independent-particle (shell) model calculations are presented. Shell structure is predicted to manifest itself through discontinuities in the single-particle level density at the Fermi energy and through variatons in the occupancy of the valence orbitals. These predictions are examined through combinatorial calculations performed with the Grover [Phys. Rev., 157, 832(1967), 185 1303(1969)] odometer method. Before the discussion of the experimenta results, statistical mechanical level densities for spherical nuclei are reviewed. After consideration of deformed nuclei, the conclusions resulting from this work are drawn. 7 figures, 3 tables

  8. Nuclear level mixing resonance spectroscopy

    International Nuclear Information System (INIS)

    Coussement, R.; Put, P.; Scheveneels, G.; Hardeman, F.

    1985-01-01

    The existent methods for measuring quadrupole interactions are not suited to nuclei with lifetimes in the micro-seconds to minutes region. AD/NQR, a possible candidate in this lifetime gap, has not yet succeeded in overcoming its predicted difficulties. A new resonant method, recently developed and based on the principles of level mixing (cfr atomic spectroscopy) covers this less accessible lifetime range. Many other kinds of resonances can be described according to the level mixing formalism. The particular example of NMR as a level mixing resonance (LMR) is discussed. The underlying theory of LMR and its important consequences, leading to some interesting features of the method, is briefly formulated. Two successfully performed measurements demonstrate the feasibility and the predicted characteristics of this new promising method. (orig.)

  9. Nuclear moment of inertia and spin distribution of nuclear levels

    International Nuclear Information System (INIS)

    Alhassid, Y.; Fang, L.; Liu, S.; Bertsch, G.F.

    2005-01-01

    We introduce a simple model to calculate the nuclear moment of inertia at finite temperature. This moment of inertia describes the spin distribution of nuclear levels in the framework of the spin-cutoff model. Our model is based on a deformed single-particle Hamiltonian with pairing interaction and takes into account fluctuations in the pairing gap. We derive a formula for the moment of inertia at finite temperature that generalizes the Belyaev formula for zero temperature. We show that a number-parity projection explains the strong odd-even effects observed in shell model Monte Carlo studies of the nuclear moment of inertia in the iron region

  10. A Robust Control Scheme for Medium-Voltage-Level DVR Implementation

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, Poh Chiang; Li, Yun Wei

    2007-01-01

    of Hinfin controller weighting function selection, inner current loop tuning, and system disturbance rejection capability is presented. Finally, the designed control scheme is extensively tested on a laboratory 10-kV MV-level DVR system with varying voltage sag (balanced and unbalanced) and loading (linear....../nonlinear load and induction motor load) conditions. It is shown that the proposed control scheme is effective in both balanced and unbalanced sag compensation and load disturbance rejection, as its robustness is explicitly specified....

  11. 'Level-level correlation and absorption in nuclear reactions'

    International Nuclear Information System (INIS)

    Hussein, M.S.

    Level-level correlation (LLC) in nuclear reactions is discussed in general and it is shown that in the presence of LLC, N sub(μ) = Σ/g μa/ 2 > divided by gamma μ T tilde, where T tilde is the average absorption in the eigen channels [pt

  12. Water level monitoring device in nuclear reactor

    International Nuclear Information System (INIS)

    Miura, Kiyohide; Otake, Tomohiro.

    1988-01-01

    Purpose: To monitor the water level in a pressure vessel of BWR type nuclear reactors at high accuracy by improving the compensation functions. Constitution: In the conventional water level monitor in a nuclear reactor, if the pressure vessel is displaced by the change of the pressure in the reactor or the temperature of the reactor water, the relative level of the reference water head in a condensation vessel is changed to cause deviation between the actual water level and the indicated water level to reduce the monitoring accuracy. According to the invention, means for detecting the position of the reference water head and means for detection the position in the condensation vessel are disposed to the pressure vessel. Then, relative positional change between the condensation vessel and the reference water head is calculated based on detection sinals from both of the means. The water level is compensated and calculated by water level calculation means based on the relative positional change, water level signals from the level gage and the pressure signals from the pressure gage. As a result, if the pressure vessel is displaced due to the change of the temperature or pressure, it is possible to measure the reactor water level accurately thereby remakably improve the reliability for the water level control in the nuclear reactor. (Horiuchi, T.)

  13. Nuclear transmutation of actinides other than fuel as a radioactive waste management scheme

    International Nuclear Information System (INIS)

    Cecille, L.; Hage, W.; Hettinger, H.; Mannone, F.; Mousty, F.; Schmidt, E.; Sola, A.; Huber, B.; Koch, L.

    1977-01-01

    The bulk of fission products in the high-level waste (HLW) decays to innocuous hazard levels within about 600 years. Actinide waste and a few fission products however represent a potential risk up to some hundreds of thousand of years. An alternative to the disposal of the whole HLW in geological formations is its fractionation, a nuclear transmutation of long-lived isotopes in fission reactors and a geological disposal of the other components. This solution would decrease the potential long-term risks of the geological waste disposal and would also accomodate to the demand of public opinion. The results of studies related to this management scheme are outlined with special reference to areas, where additional effort is required for realistic cost/benefit evaluations. Reactor physics calculations demonstrated the feasibility of actinide incineration in thermal and fast reactors. Obtained transmutation rates are sufficiently high to garantee acceptably small actinide inventories in the reactor in the case of self-generated actinide recycling. It appears that fast breeders could be used as transmutation devices without major additional reactor devlopment work. The thermal power rating of actinide fuel elements and the contribution of actinides and of minor amounts of lanthanide impurities to the neutron economy of the reactor has been evaluated. Sensitivity studies indicated that the results are dependent on the reactor operation mode and on the accuracy of the nuclear data. These calculations permitted the identification of isotopes for which cross section masurements and improved theoretical methods are required. The chemical separation of actinides from the HLW with the envisaged decontamination factors is being studied by solvent extraction and precipitation techniques using waste simulates and samples of high activity waste from European reprocessing plants. Up to now, the obtained results do not yet allow a definitive judgement on the feasibility of actinides

  14. A Study on the Security Levels of Spread-Spectrum Embedding Schemes in the WOA Framework.

    Science.gov (United States)

    Wang, Yuan-Gen; Zhu, Guopu; Kwong, Sam; Shi, Yun-Qing

    2017-08-23

    Security analysis is a very important issue for digital watermarking. Several years ago, according to Kerckhoffs' principle, the famous four security levels, namely insecurity, key security, subspace security, and stego-security, were defined for spread-spectrum (SS) embedding schemes in the framework of watermarked-only attack. However, up to now there has been little application of the definition of these security levels to the theoretical analysis of the security of SS embedding schemes, due to the difficulty of the theoretical analysis. In this paper, based on the security definition, we present a theoretical analysis to evaluate the security levels of five typical SS embedding schemes, which are the classical SS, the improved SS (ISS), the circular extension of ISS, the nonrobust and robust natural watermarking, respectively. The theoretical analysis of these typical SS schemes are successfully performed by taking advantage of the convolution of probability distributions to derive the probabilistic models of watermarked signals. Moreover, simulations are conducted to illustrate and validate our theoretical analysis. We believe that the theoretical and practical analysis presented in this paper can bridge the gap between the definition of the four security levels and its application to the theoretical analysis of SS embedding schemes.

  15. Liquid level measurement in high level nuclear waste slurries

    International Nuclear Information System (INIS)

    Weeks, G.E.; Heckendorn, F.M.; Postles, R.L.

    1990-01-01

    Accurate liquid level measurement has been a difficult problem to solve for the Defense Waste Processing Facility (DWPF). The nuclear waste sludge tends to plug or degrade most commercially available liquid-level measurement sensors. A liquid-level measurement system that meets demanding accuracy requirements for the DWPF has been developed. The system uses a pneumatic 1:1 pressure repeater as a sensor and a computerized error correction system. 2 figs

  16. Disposal of high level nuclear wastes: Thermodynamic equilibrium and environment ethics

    Institute of Scientific and Technical Information of China (English)

    RANA Mukhtar Ahmed

    2009-01-01

    Contamination of soil, water or air, due to a failure of containment or disposal of high level nuclear wastes, can potentially cause serious hazards to the environment or human health. Essential elements of the environment and radioactivity dangers to it are illustrated. Issues of high level nuclear waste disposal are discussed with a focus on thermodynamic equilibrium and environment ethics. Major aspects of the issues are analyzed and described briefly to build a perception of risks involved and ethical implications. Nuclear waste containment repository should be as close as possible to thermodynamic equilibrium. A clear demonstration about safety aspects of nuclear waste management is required in gaining public and political confidence in any possible scheme of permanent disposal. Disposal of high level nuclear waste offers a spectrum of environment connected challenges and a long term future of nuclear power depends on the environment friendly solution of the problem of nuclear wastes.

  17. Disposal of high level nuclear wastes: thermodynamic equilibrium and environment ethics

    International Nuclear Information System (INIS)

    Rana, M.A.

    2009-01-01

    Contamination of soil, water or air, due to a failure of containment or disposal of high level nuclear wastes, can potentially cause serious hazards to the environment or human health. Essential elements of the environment and radioactivity dangers to it are illustrated. Issues of high level nuclear waste disposal are discussed with a focus on thermodynamic equilibrium and environment ethics. Major aspects of the issues are analyzed and described briefly to build a perception of risks involved and ethical implications. Nuclear waste containment repository should be as close as possible to thermodynamic equilibrium. A clear demonstration about safety aspects of nuclear waste management is required in gaining public and political confidence in any possible scheme of permanent disposal. Disposal of high level nuclear waste offers a spectrum of environment connected challenges and a long term future of nuclear power depends on the environment friendly solution of the problem of nuclear wastes. (authors)

  18. A resolution adaptive deep hierarchical (RADHicaL) learning scheme applied to nuclear segmentation of digital pathology images.

    Science.gov (United States)

    Janowczyk, Andrew; Doyle, Scott; Gilmore, Hannah; Madabhushi, Anant

    2018-01-01

    Deep learning (DL) has recently been successfully applied to a number of image analysis problems. However, DL approaches tend to be inefficient for segmentation on large image data, such as high-resolution digital pathology slide images. For example, typical breast biopsy images scanned at 40× magnification contain billions of pixels, of which usually only a small percentage belong to the class of interest. For a typical naïve deep learning scheme, parsing through and interrogating all the image pixels would represent hundreds if not thousands of hours of compute time using high performance computing environments. In this paper, we present a resolution adaptive deep hierarchical (RADHicaL) learning scheme wherein DL networks at lower resolutions are leveraged to determine if higher levels of magnification, and thus computation, are necessary to provide precise results. We evaluate our approach on a nuclear segmentation task with a cohort of 141 ER+ breast cancer images and show we can reduce computation time on average by about 85%. Expert annotations of 12,000 nuclei across these 141 images were employed for quantitative evaluation of RADHicaL. A head-to-head comparison with a naïve DL approach, operating solely at the highest magnification, yielded the following performance metrics: .9407 vs .9854 Detection Rate, .8218 vs .8489 F -score, .8061 vs .8364 true positive rate and .8822 vs 0.8932 positive predictive value. Our performance indices compare favourably with state of the art nuclear segmentation approaches for digital pathology images.

  19. On expectation values for nuclear energy levels

    International Nuclear Information System (INIS)

    De Wet, J.A.

    1978-01-01

    The nuclear model is built up by constructing measured states, including the ground state, from the vacuum state. All states are, however, not accessible from the ground state so that selection rules may be found which at the same time impose even more stringent conditions on the labelling of energy levels. These are the subject of this paper

  20. Synchronised PWM Schemes for Three-level Inverters with Zero Common-mode Voltage

    DEFF Research Database (Denmark)

    Oleschuk, Valentin; Blaabjerg, Frede

    2002-01-01

    This paper presents results of analysis and comparison of novel synchronised schemes of pulsewidth modulation (PWM), applied to three-level voltage source inverters with control algorithms providing elimination of the common-mode voltage. The proposed approach is based on a new strategy of digital...

  1. Radiation levels in nuclear diagnostic examinations

    International Nuclear Information System (INIS)

    Vermeulen, A.M.T.I.

    1987-01-01

    To estimate the risks for a pregnant radiological worker, radiation level measurements are executed for common nuclear diagnostic techniques. These measurements are combined with the time which the radiologic worker is present during the performance of the diagnostic techniques. It is concluded that a radiologic worker is receiving less than 5 mSv during pregnancy. This is the case with in vivo determination in a department of nuclear medicine with common diagnostic techniques. Reduction of radiation doses during pregnancy is possible by reduction of heart function examinations, skeletal examinations and brain scans. 1 figure; 13 tabs

  2. Possibility of combining nuclear level pumping in plasma with lasing in solid

    International Nuclear Information System (INIS)

    Karamyan, S.A.; Carroll, J.J.

    2002-01-01

    Nuclear isomers can be used for the storage and release of 'clean' nuclear energy, and the visible schemes are discussed. Resonance between the atomic and nuclear transitions may be manifested in a form of the hybridization of atomic-nuclear excitation at the appropriate case. The nuclear levels - candidates for triggering via atomic transitions are described. A variety of the ionization states and atomic-shell configurations arises in hot plasma generated by the short powerful pulse of laser light. The nonradiative conversion of the ionization energy within atom can be suppressed in the hot-plasma surroundings. Time-scales of different processes in nuclear, atomic and condensed-matter subsystems are compared. The processes of fast ionization in solid, X-ray radiance in plasma, sample melting and recrystallisation may precede nuclear fluorescence. Time-scale shorter 0.1 ns makes this sequence promising for the group excitation of short-lived modes in nuclear subsystem

  3. Self consitent description of nuclear level densitities

    International Nuclear Information System (INIS)

    Barranco, M.; Treiner, J.

    1980-03-01

    We present a self consistent calculation of the nuclear level density based on a generalization to finite temperature of a modified Thomas-Fermi method. A simple expression is derived for the so-called level density parameter a entering the expression of the density of states Xi(E)=Esup(-5/4)e 2 √aE and relating the excitation energy to the temperature E=a T 2 , in terms of nucleons equilibrium densities at T=0 only. One thus avoids the difficulty of adding external constraints to calculate isolated nuclei at finite temperature which are shown to be unstable against particle emission. The role of the nuclear surface is discussed. It is shown that the effective mass of the interaction plays a crucial role in determining the value of a and comparison with experiment confirms the value m*/m > = 1 near the Fermi level obtained through more microscopic analysis

  4. Malfunction diagnosis and applications of stable adaptive schemes for a nuclear reactor system

    International Nuclear Information System (INIS)

    Fukuda, Toshio; Shibata, Heki.

    1979-01-01

    Malfunction diagnosis concerns a method to detect the abnormal phenomena during nuclear reactor operations, while stable adaptive schemes does the application of Model Reference Adaptive System (MRAS) to the nonlinear dynamics of a reactor for parameter identification and control. The new method for the malfunction diagnosis consists of the following ideas; an index defined as the sum of ratios of the square of a factor score to the contribution weight of the factor, which is evaluated by applying the multi-factor analysis technique to the data of the state of nuclear reactor systems like neutron flux, temperature, flow rate and so on. The excess of the index over some given threshold shows the reactor system would be in an abnormal state. Then a theory of optimal filtering by Kalman with the aid of the stochastic approximation is applied to estimate the neutron flux distribution at its abnormal state and subsequently the squared sum of difference between desirable and estimated flux distributions shows the spot at which the abnormal phenomena would have occurred in terms of the peak of its distribution. Parameter identification and adaptive control schemes are presented for a point reactor and a loosely-coupled-core reactor with internal feedbacks which lead to the nonlinearity of the overall system. Both schemes are shown stable with new representations of the systems, which correspond to the nonminimal system representation, in the vein of the MRAS via the Lyapunov's method. For the sake of the parameter identification, model parameters can be adjusted adaptively as soon as measurements start, while plant parameters can also adaptively be compensated through control input to reduce the output error between the model and the plant for the case of the adaptive control. Some experiments of parameter identification for the thermal-hydraulic system are carried out successfully using a simplified channel in which flow rate is varied in a binary form. (J.P.N.)

  5. Discrete level schemes and their gamma radiation branching ratios (CENPL-DLS): Pt.2

    Energy Technology Data Exchange (ETDEWEB)

    Limin, Zhang; Zongdi, Su; Zhengjun, Sun [Chinese Nuclear Data Center, Beijing, BJ (China)

    1996-06-01

    The DLS data files contains the data and information of nuclear discrete levels and gamma rays. At present, it has 79461 levels and 93177 gamma rays for 1908 nuclides. The DLS sub-library has been set up at the CNDC, and widely used for nuclear model calculation and other field. the DLS management retrieval code DLS is introduced and an example is given for {sup 56}Fe. (1 tab.).

  6. A SCHEME FOR TEMPLATE SECURITY AT FEATURE FUSION LEVEL IN MULTIMODAL BIOMETRIC SYSTEM

    Directory of Open Access Journals (Sweden)

    Arvind Selwal

    2016-09-01

    Full Text Available Biometric is the science of human recognition based upon using their biological, chemical or behavioural traits. These systems are used in many real life applications simply from biometric based attendance system to providing security at very sophisticated level. A biometric system deals with raw data captured using a sensor and feature template extracted from raw image. One of the challenges being faced by designers of these systems is to secure template data extracted from the biometric modalities of the user and protect the raw images. To minimize spoof attacks on biometric systems by unauthorised users one of the solutions is to use multi-biometric systems. Multi-modal biometric system works by using fusion technique to merge feature templates generated from different modalities of the human. In this work a new scheme is proposed to secure template during feature fusion level. Scheme is based on union operation of fuzzy relations of templates of modalities during fusion process of multimodal biometric systems. This approach serves dual purpose of feature fusion as well as transformation of templates into a single secured non invertible template. The proposed technique is cancelable and experimentally tested on a bimodal biometric system comprising of fingerprint and hand geometry. Developed scheme removes the problem of an attacker learning the original minutia position in fingerprint and various measurements of hand geometry. Given scheme provides improved performance of the system with reduction in false accept rate and improvement in genuine accept rate.

  7. High-spin level scheme of odd-odd 142Pm

    International Nuclear Information System (INIS)

    Liu Minliang; Zhang Yuhu; Zhou Xiaohong; He Jianjun; Guo Yingxiang; Lei Xiangguo; Huang Wenxue; Liu Zhong; Luo Yixiao; Feng Xichen; Zhang Shuangquan; Xu Xiao; Zheng Yong; Luo Wanju

    2002-01-01

    The level structure of doubly odd nucleus 142 Pm has been studied via the 128 Te( 19 F, 5nγ) 142 Pm reaction in the energy region from 75 to 95 MeV. In-beam γ rays were measured including the excited function, γ-ray singles and γ-γ coincidences in experiment. The level scheme of 142 Pm has been extended up to excitation energy of 7030.0 keV including 25 new γ rays and 13 new levels. Based on the measured γ-ray anisotropies, the level spins in 142 Pm have been suggested

  8. High-level nuclear waste disposal

    International Nuclear Information System (INIS)

    Burkholder, H.C.

    1985-01-01

    The meeting was timely because many countries had begun their site selection processes and their engineering designs were becoming well-defined. The technology of nuclear waste disposal was maturing, and the institutional issues arising from the implementation of that technology were being confronted. Accordingly, the program was structured to consider both the technical and institutional aspects of the subject. The meeting started with a review of the status of the disposal programs in eight countries and three international nuclear waste management organizations. These invited presentations allowed listeners to understand the similarities and differences among the various national approaches to solving this very international problem. Then seven invited presentations describing nuclear waste disposal from different perspectives were made. These included: legal and judicial, electric utility, state governor, ethical, and technical perspectives. These invited presentations uncovered several issues that may need to be resolved before high-level nuclear wastes can be emplaced in a geologic repository in the United States. Finally, there were sixty-six contributed technical presentations organized in ten sessions around six general topics: site characterization and selection, repository design and in-situ testing, package design and testing, disposal system performance, disposal and storage system cost, and disposal in the overall waste management system context. These contributed presentations provided listeners with the results of recent applied RandD in each of the subject areas

  9. Study of nuclear level densities for exotic nuclei

    International Nuclear Information System (INIS)

    Nasrabadi, M. N.; Sepiani, M.

    2012-01-01

    Nuclear level density is one of the properties of nuclei with widespread applications in astrophysics and nuclear medicine. Since there has been little experimental and theoretical research on the study of nuclei which are far from stability line, studying nuclear level density for these nuclei is of crucial importance. Also, as nuclear level density is an important input for nuclear research codes, hence studying the methods for calculation of this parameter is essential. Besides introducing various methods and models for calculating nuclear level density for practical applications, we used exact spectra distribution (SPDM) for determining nuclear level density of two neutron and proton enriched exotic nuclei with the same mass number.

  10. Practical Calculational Scheme Implementing the Wilsonian RG Results for Nuclear Effective Field Theory Including Pions

    International Nuclear Information System (INIS)

    Kubo, H.; Harada, K.; Sakaeda, T.; Yamamoto, Y.

    2013-01-01

    On the basis of the Wilsonian renormalization group (WRG) analysis of nuclear effective field theory (NEFT) including pions, we propose a practical calculational scheme in which the short-distance part of one-pion exchange (S-OPE) is removed and represented as contact terms. The long-distance part of one-pion exchange (L-OPE) is treated as perturbation. The use of dimensional regularization (DR) for diagrams consisting only of contact interactions considerably simplifies the calculation of scattering amplitude and the renormalization group equations. NLO results for nucleon-nucleon elastic scattering in the S-waves are obtained and compared with experiments. A brief comment on NNLO calculations is given. (author)

  11. Macro-level integrated renewable energy production schemes for sustainable development

    International Nuclear Information System (INIS)

    Subhadra, Bobban G.

    2011-01-01

    The production of renewable clean energy is a prime necessity for the sustainable future existence of our planet. However, because of the resource-intensive nature, and other challenges associated with these new generation renewable energy sources, novel industrial frameworks need to be co-developed. Integrated renewable energy production schemes with foundations on resource sharing, carbon neutrality, energy-efficient design, source reduction, green processing plan, anthropogenic use of waste resources for the production green energy along with the production of raw material for allied food and chemical industries is imperative for the sustainable development of this sector especially in an emission-constrained future industrial scenario. To attain these objectives, the scope of hybrid renewable production systems and integrated renewable energy industrial ecology is briefly described. Further, the principles of Integrated Renewable Energy Park (IREP) approach, an example for macro-level energy production, and its benefits and global applications are also explored. - Research highlights: → Discusses the need for macro-level renewable energy production schemes. → Scope of hybrid and integrated industrial ecology for renewable energy production. → Integrated Renewable Energy Parks (IREPs): A macro-level energy production scheme. → Discusses the principle foundations and global applications of IREPs. → Describes the significance of IREPs in the carbon-neutral future business arena.

  12. Discrete level schemes and their gamma radiation branching ratios (CENPL-DLS). Pt. 1

    International Nuclear Information System (INIS)

    Su Zongdi; Zhang Limin; Zhou Chunmei; Sun Zhengjun

    1994-01-01

    The DLS data file, which is a sub-library (version 1) of Chinese Evaluated Nuclear Parameter Library (CENPL), consists of data and information of discrete levels and gamma radiations. The data and information of this data file are translated from the Evaluated Nuclear Structure Data File (ENSDF). The transforming code from ENSDF to DLS was written. In the DLS data file, there are the data on discrete levels with determinate energy and their gamma radiations. At present, this file contains the data of 79456 levels and 100411 gammas for 1908 nuclides

  13. A proposal of new nuclear communication scheme based on qualitative research

    International Nuclear Information System (INIS)

    Yagi, Ekou; Takahashi, Makoto; Kitamura, Masaharu

    2007-01-01

    An action research project called dialogue forum has been conducted in this study. The essential constituent of the project is a series of repetitive dialogue sessions carried out by lay citizens, nuclear experts, and a facilitator. One important feature of the project is that the study has been conducted based on the qualitative research methodology. The changes in opinions and attitude of the dialogue participants have been analyzed by an ethno-methodological approach. The observations are summarized as follows. The opinions of the citizen participants showed a significant shift from emotional to practical representations along with the progression of the dialogue sessions. Meanwhile, their attitude showed a marked tendency from problem-statement-oriented to problem-solving-oriented representation. On the other hand, the statements of the expert participants showed a significant shift from expert-based to citizen-based risk recognition and description, and their attitude showed a clear tendency from teaching-oriented to colearning-oriented thinking. These changes of opinions and attitude have been interpreted as a coevolving rather than a single process. It can be stressed that this type of change is most important for the reestablishment of mutual trust between the citizens and the nuclear experts. In this regard The Process Model of Coevolution of Risk Recognition' has been proposed as a guideline for developing a new scheme of public communication concerning nuclear technology. The proposed process model of coevolution of risk recognition is regarded to be essential for appropriate relationship management between nuclear technology and society in the near future. (author)

  14. Principal scheme of preventive maintenance support system for nuclear power plants

    International Nuclear Information System (INIS)

    Nishiyama, Takuya; Terano, Takao; Yokoo, Takeshi; Shinohara, Yasushi

    1985-01-01

    It is of great importance to turn lessons learned from abnormal event experiences to advantage as well as taking apriori actions for prevention of abnormal events in nuclear power plants. From this point of view, a consultation system, named as Preventive Maintenance Support System (PMSS), which is to possess accumulated knowledges drawn from the past abnormal events in nuclear power plants infer occurrences, factors and developments of abnormal events and recommend preventive countermeasures on the basis of the knowledges, has been proposed. This report presents the principal scheme of PMSS. To begin with, following to the discussion of the purpose and use of PMSS, the fundamental functions PMSS should perform are specified. They are (1) event factors analyzation, (2) event prediction (event development estimation and analogous event estimation), (3) event significance evaluation and (4) preventive countermeasures presentation. In the next place, it is asserted that such a system should be constructed as a knowledge engineering one. Then, the R and D subjects and related schedule for PMSS are set up. (author)

  15. The scheme optimization and management innovation for the first containment integrated in-service test of nuclear power plant

    International Nuclear Information System (INIS)

    Wang Haiwei; Yang Gang

    2014-01-01

    The containment integrated test is a large-scale, high risk and very difficult test in pressurized water reactor nuclear power plants. By simulating peak pressure inside the containment in DESIGN-BASIS accident conditions, measuring the total leakage rate of the containment with the peak pressure, and implementing the structure inspection test on several pressure levels, the containment's performance can be verified. Containment integrated test is an important witness point supervised by NNSA. The test results crucially decide the reactor to be started or not. The containment integrated test in 301 overhaul is the first in-service test of Unit 3. By the experience of the same 6 former tests in Qinshan Second Nuclear Power Plant and the feedback from other plants, the test scheme get more scientific and the organization management more standardized. This article discusses the containment integrated test in 301 overhaul and summarizes the experience to provide some references for the following containment integrated tests in the future. (authors)

  16. The effect of hearing aid signal-processing schemes on acceptable noise levels: perception and prediction.

    Science.gov (United States)

    Wu, Yu-Hsiang; Stangl, Elizabeth

    2013-01-01

    The acceptable noise level (ANL) test determines the maximum noise level that an individual is willing to accept while listening to speech. The first objective of the present study was to systematically investigate the effect of wide dynamic range compression processing (WDRC), and its combined effect with digital noise reduction (DNR) and directional processing (DIR), on ANL. Because ANL represents the lowest signal-to-noise ratio (SNR) that a listener is willing to accept, the second objective was to examine whether the hearing aid output SNR could predict aided ANL across different combinations of hearing aid signal-processing schemes. Twenty-five adults with sensorineural hearing loss participated in the study. ANL was measured monaurally in two unaided and seven aided conditions, in which the status of the hearing aid processing schemes (enabled or disabled) and the location of noise (front or rear) were manipulated. The hearing aid output SNR was measured for each listener in each condition using a phase-inversion technique. The aided ANL was predicted by unaided ANL and hearing aid output SNR, under the assumption that the lowest acceptable SNR at the listener's eardrum is a constant across different ANL test conditions. Study results revealed that, on average, WDRC increased (worsened) ANL by 1.5 dB, while DNR and DIR decreased (improved) ANL by 1.1 and 2.8 dB, respectively. Because the effects of WDRC and DNR on ANL were opposite in direction but similar in magnitude, the ANL of linear/DNR-off was not significantly different from that of WDRC/DNR-on. The results further indicated that the pattern of ANL change across different aided conditions was consistent with the pattern of hearing aid output SNR change created by processing schemes. Compared with linear processing, WDRC creates a noisier sound image and makes listeners less willing to accept noise. However, this negative effect on noise acceptance can be offset by DNR, regardless of microphone mode

  17. Excitation energy and angular momentum dependence of the nuclear level densities

    International Nuclear Information System (INIS)

    Razavi, R.; Kakavand, T.; Behkami, A. N.

    2007-01-01

    We have investigated the excitation energy (E) dependence of nuclear level density for Bethe formula and constant temperature model. The level density parameter aa nd the back shifted energy from the Bethe formula are obtained by fitting the complete level schemes. Also the level density parameters from the constant temperature model have been determined for several nuclei. we have shown that the microscopic theory provides more precise information on the nuclear level densities. On the other hand, the spin cut-off parameter and effective moment of inertia are determined by studying of the angular momentum (J) dependence of the nuclear level density, and effective moment of inertia is compared with rigid body value.

  18. Federal and state regulatory schemes affecting liability for high-level waste transportation incidents: opportunities for clarification and amendment

    International Nuclear Information System (INIS)

    Friel, L.E.; Livingston-Behan, E.A.

    1985-01-01

    The Price-Anderson Act of 1957 provides extensive public liability coverage in the event of a serious accident involving the transportation of nuclear materials to or from certain federally-licensed, or federal contractor-operated facilities. While actual liability for a nuclear incident and the extent of damages are usually determined by state law, the Act establishes a comprehensive system for the payment of such damages. Despite the federally-mandated scheme for liability coverage several aspects of the Act's application to transportation to a permanent repository have not yet been settled and are open to various interpretations. Some areas of uncertainty apply not only to future waste transport to a repository, but also to current transportation activities, and include: coverage for emergency response and clean-up costs; coverage for precautionary evacuations; and the federal government's financial liability. The need to address liability issues is also increasingly recognized at the state level. The state laws which are used to determine liability and the extent of damages in the event of a transportation accident vary widely among states and significantly affect the compensation that an injured person will receive under the provisions of the Price-Anderson Act. Areas of state law deserving special attention include: standards for determining liability; statutes of limitations; standards for proof of causation; state sovereign immunity statutes; and recovery of unique emergency response costs

  19. Effect of pairing in nuclear level density at low temperatures

    International Nuclear Information System (INIS)

    Rhine Kumar, A.K.; Modi, Swati; Arumugam, P.

    2013-01-01

    The nuclear level density (NLD) has been an interesting topic for researchers, due its importance in many aspects of nuclear physics, nuclear astrophysics, nuclear medicine, and other applied areas. The calculation of NLD helps us to understand the energy distribution of the excited levels of nuclei, entropy, specific heat, reaction cross sections etc. In this work the effect of temperature and pairing on level-density of the nucleus 116 Sn has been studied

  20. Visual privacy by context: proposal and evaluation of a level-based visualisation scheme.

    Science.gov (United States)

    Padilla-López, José Ramón; Chaaraoui, Alexandros Andre; Gu, Feng; Flórez-Revuelta, Francisco

    2015-06-04

    Privacy in image and video data has become an important subject since cameras are being installed in an increasing number of public and private spaces. Specifically, in assisted living, intelligent monitoring based on computer vision can allow one to provide risk detection and support services that increase people's autonomy at home. In the present work, a level-based visualisation scheme is proposed to provide visual privacy when human intervention is necessary, such as at telerehabilitation and safety assessment applications. Visualisation levels are dynamically selected based on the previously modelled context. In this way, different levels of protection can be provided, maintaining the necessary intelligibility required for the applications. Furthermore, a case study of a living room, where a top-view camera is installed, is presented. Finally, the performed survey-based evaluation indicates the degree of protection provided by the different visualisation models, as well as the personal privacy preferences and valuations of the users.

  1. Selecting a distillation scheme for purifying ditolymethane for a nuclear heat source

    International Nuclear Information System (INIS)

    Garanin, V.I.; Stychinskii, G.F.; Chukhlov, G.Z.; Smirnova, V.S.

    1989-01-01

    Ditolymethane can be used as a coolant in nuclear heat plants, although it needs ongoing purification from radiolytic products, including low-boiling and high-boiling components. Periodic distillation to remove radiolytic products represents world practice. The objective of this study was to develop a distillation system less laborious to service, simpler to automate, and costing less to operate. A continuous-flow plant can have those advantages if one could use the heat from the first loop in the plant (200-240C) to evaporate the ditolymethane and the low-boiling components instead of the more expensive electrical power, while the vapor could be condensed by cheaper air cooling to +30C instead of water cooling, while one could reduce the loss of ditolymethane with the wastes and almost eliminate the loss of low-boiling components in the vacuum pump. The laboratory tests were based on outgassed ditholymethane coolant from the first loop in the ARBUS nuclear heat plant, which had the following mass-fraction composition: ditolylmethane 82 ± 1, low-boiling components 2.3 ± 0.2, and high-boiling ones 16 ± 1%. The low-boiling components included benzene, toluene, xylene, and four unidentified compounds. The high-boiling ones included compounds containing three or more benzene rings and having a mean molecular weight 450. Continuous purification from these components and water was examined in two ways. In a one-stage system, the two types of organic component and the water are removed under a common vacuum by sequential partial condensation from the common vapor flow as the temperature is reduced. The two-stage scheme differed in that the low-boiling components and the water were removed at a lower vacuum (first stage) and the high-boiling ones at a higher vacuum (second stage)

  2. Economic sustainability, water security and multi-level governance of local water schemes in Nepal

    Directory of Open Access Journals (Sweden)

    Emma Hakala

    2017-07-01

    Full Text Available This article explores the role of multi-level governance and power structures in local water security through a case study of the Nawalparasi district in Nepal. It focuses on economic sustainability as a measure to address water security, placing this thematic in the context of a complicated power structure consisting of local, district and national administration as well as external development cooperation actors. The study aims to find out whether efforts to improve the economic sustainability of water schemes have contributed to water security at the local level. In addition, it will consider the interactions between water security, power structures and local equality and justice. The research builds upon survey data from the Nepalese districts of Nawalparasi and Palpa, and a case study based on interviews and observation in Nawalparasi. The survey was performed in water schemes built within a Finnish development cooperation programme spanning from 1990 to 2004, allowing a consideration of the long-term sustainability of water management projects. This adds a crucial external influence into the intra-state power structures shaping water management in Nepal. The article thus provides an alternative perspective to cross-regional water security through a discussion combining transnational involvement with national and local points of view.

  3. A novel two-level dynamic parallel data scheme for large 3-D SN calculations

    International Nuclear Information System (INIS)

    Sjoden, G.E.; Shedlock, D.; Haghighat, A.; Yi, C.

    2005-01-01

    We introduce a new dynamic parallel memory optimization scheme for executing large scale 3-D discrete ordinates (Sn) simulations on distributed memory parallel computers. In order for parallel transport codes to be truly scalable, they must use parallel data storage, where only the variables that are locally computed are locally stored. Even with parallel data storage for the angular variables, cumulative storage requirements for large discrete ordinates calculations can be prohibitive. To address this problem, Memory Tuning has been implemented into the PENTRAN 3-D parallel discrete ordinates code as an optimized, two-level ('large' array, 'small' array) parallel data storage scheme. Memory Tuning can be described as the process of parallel data memory optimization. Memory Tuning dynamically minimizes the amount of required parallel data in allocated memory on each processor using a statistical sampling algorithm. This algorithm is based on the integral average and standard deviation of the number of fine meshes contained in each coarse mesh in the global problem. Because PENTRAN only stores the locally computed problem phase space, optimal two-level memory assignments can be unique on each node, depending upon the parallel decomposition used (hybrid combinations of angular, energy, or spatial). As demonstrated in the two large discrete ordinates models presented (a storage cask and an OECD MOX Benchmark), Memory Tuning can save a substantial amount of memory per parallel processor, allowing one to accomplish very large scale Sn computations. (authors)

  4. Solving the Sea-Level Equation in an Explicit Time Differencing Scheme

    Science.gov (United States)

    Klemann, V.; Hagedoorn, J. M.; Thomas, M.

    2016-12-01

    In preparation of coupling the solid-earth to an ice-sheet compartment in an earth-system model, the dependency of initial topography on the ice-sheet history and viscosity structure has to be analysed. In this study, we discuss this dependency and how it influences the reconstruction of former sea level during a glacial cycle. The modelling is based on the VILMA code in which the field equations are solved in the time domain applying an explicit time-differencing scheme. The sea-level equation is solved simultaneously in the same explicit scheme as the viscoleastic field equations (Hagedoorn et al., 2007). With the assumption of only small changes, we neglect the iterative solution at each time step as suggested by e.g. Kendall et al. (2005). Nevertheless, the prediction of the initial paleo topography in case of moving coastlines remains to be iterated by repeated integration of the whole load history. The sensitivity study sketched at the beginning is accordingly motivated by the question if the iteration of the paleo topography can be replaced by a predefined one. This study is part of the German paleoclimate modelling initiative PalMod. Lit:Hagedoorn JM, Wolf D, Martinec Z, 2007. An estimate of global mean sea-level rise inferred from tide-gauge measurements using glacial-isostatic models consistent with the relative sea-level record. Pure appl. Geophys. 164: 791-818, doi:10.1007/s00024-007-0186-7Kendall RA, Mitrovica JX, Milne GA, 2005. On post-glacial sea level - II. Numerical formulation and comparative reesults on spherically symmetric models. Geophys. J. Int., 161: 679-706, doi:10.1111/j.365-246.X.2005.02553.x

  5. The scheme machine: A case study in progress in design derivation at system levels

    Science.gov (United States)

    Johnson, Steven D.

    1995-01-01

    The Scheme Machine is one of several design projects of the Digital Design Derivation group at Indiana University. It differs from the other projects in its focus on issues of system design and its connection to surrounding research in programming language semantics, compiler construction, and programming methodology underway at Indiana and elsewhere. The genesis of the project dates to the early 1980's, when digital design derivation research branched from the surrounding research effort in programming languages. Both branches have continued to develop in parallel, with this particular project serving as a bridge. However, by 1990 there remained little real interaction between the branches and recently we have undertaken to reintegrate them. On the software side, researchers have refined a mathematically rigorous (but not mechanized) treatment starting with the fully abstract semantic definition of Scheme and resulting in an efficient implementation consisting of a compiler and virtual machine model, the latter typically realized with a general purpose microprocessor. The derivation includes a number of sophisticated factorizations and representations and is also deep example of the underlying engineering methodology. The hardware research has created a mechanized algebra supporting the tedious and massive transformations often seen at lower levels of design. This work has progressed to the point that large scale devices, such as processors, can be derived from first-order finite state machine specifications. This is roughly where the language oriented research stops; thus, together, the two efforts establish a thread from the highest levels of abstract specification to detailed digital implementation. The Scheme Machine project challenges hardware derivation research in several ways, although the individual components of the system are of a similar scale to those we have worked with before. The machine has a custom dual-ported memory to support garbage collection

  6. Enhanced nuclear level decay in hot dense plasmas

    International Nuclear Information System (INIS)

    Gosselin, G.; Morel, P.

    2004-01-01

    A model of nuclear level decay in a plasma environment is described. Nuclear excitation and decay by photon processes, nuclear excitation by electron capture, and decay by internal conversion are taken into account. The electrons in the plasma are described by a relativistic average atom model for the bound electrons and by a relativistic Thomas-Fermi-Dirac model for the free electrons. Nuclear decay of isomeric level may be enhanced through an intermediate level lying above the isomer. An enhanced nuclear decay rate may occur for temperatures far below the excitation energy of the transition to the intermediate level. In most cases, the enhancement factor may reach several decades

  7. X-RAY ABSORPTION, NUCLEAR INFRARED EMISSION, AND DUST COVERING FACTORS OF AGNs: TESTING UNIFICATION SCHEMES

    Energy Technology Data Exchange (ETDEWEB)

    Mateos, S.; Carrera, F. J.; Alonso-Herrero, A.; Hernán-Caballero, A.; Barcons, X. [Instituto de Física de Cantabria (CSIC-Universidad de Cantabria), E-39005, Santander (Spain); Ramos, A. Asensio; Almeida, C. Ramos [Instituto de Astrofísica de Canarias, E-38205, La Laguna, Tenerife (Spain); Watson, M. G.; Blain, A. [Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Caccianiga, A.; Ballo, L. [INAF-Osservatorio Astronomico di Brera, via Brera 28, I-20121 Milano (Italy); Braito, V., E-mail: mateos@ifca.unican.es [INAF-Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate (Italy)

    2016-03-10

    We present the distributions of the geometrical covering factors of the dusty tori (f{sub 2}) of active galactic nuclei (AGNs) using an X-ray selected complete sample of 227 AGNs drawn from the Bright Ultra-hard XMM-Newton Survey. The AGNs have z from 0.05 to 1.7, 2–10 keV luminosities between 10{sup 42} and 10{sup 46} erg s{sup −1}, and Compton-thin X-ray absorption. Employing data from UKIDSS, 2MASS, and the Wide-field Infrared Survey Explorer in a previous work, we determined the rest-frame 1–20 μm continuum emission from the torus, which we model here with the clumpy torus models of Nenkova et al. Optically classified type 1 and type 2 AGNs are intrinsically different, with type 2 AGNs having, on average, tori with higher f{sub 2} than type 1 AGNs. Nevertheless, ∼20% of type 1 AGNs have tori with large covering factors, while ∼23%–28% of type 2 AGNs have tori with small covering factors. Low f{sub 2} are preferred at high AGN luminosities, as postulated by simple receding torus models, although for type 2 AGNs the effect is certainly small. f{sub 2} increases with the X-ray column density, which implies that dust extinction and X-ray absorption take place in material that share an overall geometry and most likely belong to the same structure, the putative torus. Based on our results, the viewing angle, AGN luminosity, and also f{sub 2} determine the optical appearance of an AGN and control the shape of the rest-frame ∼1–20 μm nuclear continuum emission. Thus, the torus geometrical covering factor is a key ingredient of unification schemes.

  8. Modulation Schemes of Multi-phase Three-Level Z-Source Inverters

    DEFF Research Database (Denmark)

    Gao, F.; Loh, P.C.; Blaabjerg, Frede

    2007-01-01

    different modulation requirement and output performance. For clearly illustrating the detailed modulation process, time domain analysis instead of the traditional multi-dimensional space vector demonstration is assumed which reveals the right way to insert shoot-through durations in the switching sequence...... with minimal commutation count. Lastly, the theoretical findings are verified in Matlab/PLECS simulation and experimentally using constructed laboratory prototypes.......This paper investigates the modulation schemes of three-level multiphase Z-source inverters with either two Z-source networks or single Z-source network connected between the dc sources and inverter circuitry. With the proper offset added for achieving both desired four-leg operation and optimized...

  9. Nuclear Level densities from drip line to drip line

    International Nuclear Information System (INIS)

    Hilaire, S.; Goriely, S.

    2007-01-01

    New energy-, spin-, parity-dependent level densities based on the microscopic combinatorial model are presented and compared with available experimental data as well as with other nuclear level densities usually employed in nuclear reaction codes. These microscopic level densities are made available in a table format for nearly 8500 nuclei

  10. Two-level convolution formula for nuclear structure function

    Science.gov (United States)

    Ma, Boqiang

    1990-05-01

    A two-level convolution formula for the nuclear structure function is derived in considering the nucleus as a composite system of baryon-mesons which are also composite systems of quark-gluons again. The results show that the European Muon Colaboration effect can not be explained by the nuclear effects as nucleon Fermi motion and nuclear binding contributions.

  11. Two-level convolution formula for nuclear structure function

    International Nuclear Information System (INIS)

    Ma Boqiang

    1990-01-01

    A two-level convolution formula for the nuclear structure function is derived in considering the nucleus as a composite system of baryon-mesons which are also composite systems of quark-gluons again. The results show that the European Muon Colaboration effect can not be explained by the nuclear effects as nucleon Fermi motion and nuclear binding contributions

  12. Different-Level Simultaneous Minimization Scheme for Fault Tolerance of Redundant Manipulator Aided with Discrete-Time Recurrent Neural Network.

    Science.gov (United States)

    Jin, Long; Liao, Bolin; Liu, Mei; Xiao, Lin; Guo, Dongsheng; Yan, Xiaogang

    2017-01-01

    By incorporating the physical constraints in joint space, a different-level simultaneous minimization scheme, which takes both the robot kinematics and robot dynamics into account, is presented and investigated for fault-tolerant motion planning of redundant manipulator in this paper. The scheme is reformulated as a quadratic program (QP) with equality and bound constraints, which is then solved by a discrete-time recurrent neural network. Simulative verifications based on a six-link planar redundant robot manipulator substantiate the efficacy and accuracy of the presented acceleration fault-tolerant scheme, the resultant QP and the corresponding discrete-time recurrent neural network.

  13. Study of nuclear level density parameter and its temperature dependence

    International Nuclear Information System (INIS)

    Nasrabadi, M. N.; Behkami, A. N.

    2000-01-01

    The nuclear level density ρ is the basic ingredient required for theoretical studies of nuclear reaction and structure. It describes the statistical nuclear properties and is expressed as a function of various constants of motion such as number of particles, excitation energy and angular momentum. In this work the energy and spin dependence of nuclear level density will be presented and discussed. In addition the level density parameter α will be extracted from this level density information, and its temperature and mass dependence will be obtained

  14. Storage of High Level Nuclear Waste in Germany

    Directory of Open Access Journals (Sweden)

    Dietmar P. F. Möller

    2007-01-01

    Full Text Available Nuclear energy is very often used to generate electricity. But first the energy must be released from atoms what can be done in two ways: nuclear fusion and nuclear fission. Nuclear power plants use nuclear fission to produce electrical energy. The electrical energy generated in nuclear power plants does not produce polluting combustion gases but a renewable energy, an important fact that could play a key role helping to reduce global greenhouse gas emissions and tackling global warming especially as the electricity energy demand rises in the years ahead. This could be assumed as an ideal win-win situation, but the reverse site of the medal is that the production of high-level nuclear waste outweighs this advantage. Hence the paper attempt to highlight the possible state-of-art concepts for the safe and sustaining storage of high-level nuclear waste in Germany.

  15. About efficient quasi-Newtonian schemes for variational calculations in nuclear structure

    International Nuclear Information System (INIS)

    Puddu, G.

    2009-01-01

    The Broyden-Fletcher-Goldhaber-Shanno (BFGS) quasi-Newtonian scheme is known as the most efficient scheme for variational calculations of energies. This scheme is actually a member of a one-parameter family of variational methods, known as the Broyden β-family. In some applications to light nuclei using microscopically derived effective Hamiltonians starting from accurate nucleon-nucleon potentials, we actually found other members of the same family which have better performance than the BFGS method. We also extend the Broyden β -family of algorithms to a two-parameter family of rank-three updates which has even better performances. (orig.)

  16. Two-level MOC calculation scheme in APOLLO2 for cross-section library generation for LWR hexagonal assemblies

    International Nuclear Information System (INIS)

    Petrov, Nikolay; Todorova, Galina; Kolev, Nikola; Damian, Frederic

    2011-01-01

    The accurate and efficient MOC calculation scheme in APOLLO2, developed by CEA for generating multi-parameterized cross-section libraries for PWR assemblies, has been adapted to hexagonal assemblies. The neutronic part of this scheme is based on a two-level calculation methodology. At the first level, a multi-cell method is used in 281 energy groups for cross-section definition and self-shielding. At the second level, precise MOC calculations are performed in a collapsed energy mesh (30-40 groups). In this paper, the application and validation of the two-level scheme for hexagonal assemblies is described. Solutions for a VVER assembly are compared with TRIPOLI4® calculations and direct 281g MOC solutions. The results show that the accuracy is close to that of the 281g MOC calculation while the CPU time is substantially reduced. Compared to the multi-cell method, the accuracy is markedly improved. (author)

  17. Nuclear power and low level radiation hazards

    International Nuclear Information System (INIS)

    Myers, D.K.; Newcombe, H.B.

    1979-03-01

    Even in the future, nuclear power is expected to contribute less than 1/10th of the present total population exposure to man-made radiation. By the best estimates available, the current health risks of nuclear power generation appear to be much less than those associated with the major alternative sources of energy, with the exception of natural gas which is about equally safe. Uncertainties concerning the radiation risks from nuclear power, from medical x-rays and from the effects of reduced ventillation to conserve heat appear to be less than those associated with estimates of risks from the use of coal and various other sources of energy. This is in part because of the large amount of effort devoted to studies of radiation effects. The benefits in terms of current life expectancy associated with any of the conventional or unconventional methods of power production appear to greatly outweigh the associated current health hazards. (author)

  18. New level schemes with high-spin states of 105,107,109Tc

    International Nuclear Information System (INIS)

    Luo, Y.X.; Rasmussen, J.O.; Lee, I.Y.; Fallon, P.; Hamilton, J.H.; Ramayya, A.V.; Hwang, J.K.; Gore, P.M.; Zhu, S.J.; Wu, S.C.; Ginter, T.N.; Ter-Akopian, G.M.; Daniel, A.V.; Stoyer, M.A.; Donangelo, R.; Gelberg, A.

    2004-01-01

    New level schemes of odd-Z 105,107,109 Tc are proposed based on the 252 Cf spontaneous-fission-gamma data taken with Gammasphere in 2000. Bands of levels are considerably extended and expanded to show rich spectroscopic information. Spin/parity and configuration assignments are made based on determinations of multipolarities of low-lying transitions and the level analogies to the previously reported levels, and to those of the neighboring Rh isotopes. A non-yrast negative-parity band built on the 3/2 - [301] orbital is observed for the first time in 105 Tc. A positive-parity band built on the 1/2 + [431] intruder orbital originating from the π(g 7/2 /d 5/2 ) subshells and having a strong deformation-driving effect is observed for the first time in 105 Tc, and assigned in 107 Tc. A positive-parity band built on the excited 11/2 + level, which has rather low excitation energy and predominantly decays into the 9/2 + level of the ground state band, provides evidence of triaxiality in 107,109 Tc, and probably also in 105 Tc. Rotational constants are calculated and discussed for the K=1/2 intruder bands using the Bohr-Mottelson formula. Level systematics are discussed in terms of the locations of proton Fermi levels and deformations. The band crossings of yrast positive-parity bands are observed, most likely related to h 11/2 neutron alignment. Triaxial-rotor-plus-particle model calculations performed with ε=0.32 and γ=-22.5 deg. on the prolate side of maximum triaxiality yielded the best reproduction of the excitation energies, signature splittings, and branching ratios of the positive-parity bands (except for the intruder bands) of these Tc isotopes. The significant discrepancies between the triaxial-rotor-plus-particle model calculations and experiment for the K=1/2 intruder bands in 105,107 Tc need further theoretical studies

  19. Three-dimensional coupled Monte Carlo-discrete ordinates computational scheme for shielding calculations of large and complex nuclear facilities

    International Nuclear Information System (INIS)

    Chen, Y.; Fischer, U.

    2005-01-01

    Shielding calculations of advanced nuclear facilities such as accelerator based neutron sources or fusion devices of the tokamak type are complicated due to their complex geometries and their large dimensions, including bulk shields of several meters thickness. While the complexity of the geometry in the shielding calculation can be hardly handled by the discrete ordinates method, the deep penetration of radiation through bulk shields is a severe challenge for the Monte Carlo particle transport technique. This work proposes a dedicated computational scheme for coupled Monte Carlo-Discrete Ordinates transport calculations to handle this kind of shielding problems. The Monte Carlo technique is used to simulate the particle generation and transport in the target region with both complex geometry and reaction physics, and the discrete ordinates method is used to treat the deep penetration problem in the bulk shield. The coupling scheme has been implemented in a program system by loosely integrating the Monte Carlo transport code MCNP, the three-dimensional discrete ordinates code TORT and a newly developed coupling interface program for mapping process. Test calculations were performed with comparison to MCNP solutions. Satisfactory agreements were obtained between these two approaches. The program system has been chosen to treat the complicated shielding problem of the accelerator-based IFMIF neutron source. The successful application demonstrates that coupling scheme with the program system is a useful computational tool for the shielding analysis of complex and large nuclear facilities. (authors)

  20. Experimental nuclear level densities and γ-ray strength functions in Sc and V isotopes

    International Nuclear Information System (INIS)

    Larsen, A. C.; Guttormsen, M.; Ingebretsen, F.; Messelt, S.; Rekstad, J.; Siem, S.; Syed, N. U. H.; Chankova, R.; Loennroth, T.; Schiller, A.; Voinov, A.

    2008-01-01

    The nuclear physics group at the Oslo Cyclotron Laboratory has developed a method to extract nuclear level density and γ-ray strength function from first-generation γ-ray spectra. This method is applied on the nuclei 44,45 Sc and 50,51 V in this work. The experimental level densities of 44,45 Sc are compared to calculated level densities using a microscopic model based on BCS quasiparticles within the Nilsson level scheme. The γ-ray strength functions are also compared to theoretical expectations, showing an unexpected enhancement of the γ-ray strength for low γ energies (E γ ≤3 MeV) in all the isotopes studied here. The physical origin of this enhancement is not yet understood

  1. Auxiliary System Load Schemes in Large Thermal and Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kuzle, I.; Bosnjak, D.; Pandzic, H.

    2010-01-01

    Uninterrupted auxiliary system power supply in large power plants is a key factor for normal operation, transient states, start-ups and shutdowns and particularly during fault conditions. Therefore, there are many challenges in designing the main electrical system as well as the auxiliary systems power supply. Depending upon the type of fuel used and the environmental control system required, a thermal power plant may consume as much as 10% of its total generation for auxiliary power, while a nuclear power plant may require only 4 - 6% auxiliaries. In general, the larger the power generating plant, the higher the voltage selected for the AC auxiliary electric system. Most stations in the 75 to 500 MW range utilize 4,2 kV as the base auxiliary system voltage. Large generating stations 500 - 1000 MW and more use voltage levels of 6,9 kV and more. Some single dedicated loads such as electric driven boiler feed pumps are supplied ba a 13,8 kV bus. While designing the auxiliary electric system, the following areas must be considered: motor starting requirements, voltage regulation requirements, short-circuit duty requirements, economic considerations, reliability and alternate sources. Auxiliary power supply can't be completely generalized and each situation should be studied on its own merits to determine the optimal solution. Naturally, nuclear power plants have more reliability requirements and safety design criteria. Main coolant-pump power supply and continuity of service to other vital loads deserve special attention. This paper presents an overview of some up-to-date power plant auxiliary load system concepts. The main types of auxiliary loads are described and the electric diagrams of the modern auxiliary system supply concepts are given. Various alternative sources of auxiliary electrical supply are considered, the advantages and disadvantages of these are compared and proposals are made for high voltage distribution systems around the thermal and nuclear plant

  2. An Enhanced Three-Level Voltage Switching State Scheme for Direct Torque Controlled Open End Winding Induction Motor

    Science.gov (United States)

    Kunisetti, V. Praveen Kumar; Thippiripati, Vinay Kumar

    2018-01-01

    Open End Winding Induction Motors (OEWIM) are popular for electric vehicles, ship propulsion applications due to less DC link voltage. Electric vehicles, ship propulsions require ripple free torque. In this article, an enhanced three-level voltage switching state scheme for direct torque controlled OEWIM drive is implemented to reduce torque and flux ripples. The limitations of conventional Direct Torque Control (DTC) are: possible problems during low speeds and starting, it operates with variable switching frequency due to hysteresis controllers and produces higher torque and flux ripple. The proposed DTC scheme can abate the problems of conventional DTC with an enhanced voltage switching state scheme. The three-level inversion was obtained by operating inverters with equal DC-link voltages and it produces 18 voltage space vectors. These 18 vectors are divided into low and high frequencies of operation based on rotor speed. The hardware results prove the validity of proposed DTC scheme during steady-state and transients. From simulation and experimental results, proposed DTC scheme gives less torque and flux ripples on comparison to two-level DTC. The proposed DTC is implemented using dSPACE DS-1104 control board interface with MATLAB/SIMULINK-RTI model.

  3. Recent advances in measurements of the nuclear level density

    International Nuclear Information System (INIS)

    John, Bency

    2007-01-01

    A short review of recent advances in measurements of the nuclear level density is given. First results of the inverse level density parameter - angular momentum correlation in a number of nuclei around Z∼50 shell region at an excitation energy around 0.3 MeV/nucleon are presented. Significant variations observed over and above the expected shell corrections are discussed in context of the emerging trends in microscopic calculations of the nuclear level density. (author)

  4. Scheme of fault tectonic and tectonic activity manifestation in the region of the Crimea nuclear power plant construction

    International Nuclear Information System (INIS)

    Pasynkov, A.L.

    1989-01-01

    Characteristic of fault tectonics and tectonic activity manifestation in the region of the Crimea nuclear power plant construction is presented. Mosaic-block structure of the area, predetermined by the development of diagonal systems of activated tectonic dislocations with different displacement amplitudes and different stratigraphic ranges of manifestation, was established. Strained-stressed state of the region is determined by the presence of the South-Azov zone of deep fault and Krasnogorsk-Samarlinks fault system. The presented scheme can be used as tectonic basis of seismogenic activity of the region

  5. Materials Science of High-Level Nuclear Waste Immobilization

    International Nuclear Information System (INIS)

    Weber, William J.; Navrotsky, Alexandra; Stefanovsky, S. V.; Vance, E. R.; Vernaz, Etienne Y.

    2009-01-01

    With the increasing demand for the development of more nuclear power comes the responsibility to address the technical challenges of immobilizing high-level nuclear wastes in stable solid forms for interim storage or disposition in geologic repositories. The immobilization of high-level nuclear wastes has been an active area of research and development for over 50 years. Borosilicate glasses and complex ceramic composites have been developed to meet many technical challenges and current needs, although regulatory issues, which vary widely from country to country, have yet to be resolved. Cooperative international programs to develop advanced proliferation-resistant nuclear technologies to close the nuclear fuel cycle and increase the efficiency of nuclear energy production might create new separation waste streams that could demand new concepts and materials for nuclear waste immobilization. This article reviews the current state-of-the-art understanding regarding the materials science of glasses and ceramics for the immobilization of high-level nuclear waste and excess nuclear materials and discusses approaches to address new waste streams

  6. University students' understanding level about words related to nuclear power

    International Nuclear Information System (INIS)

    Oiso, Shinichi; Watabe, Motoki

    2012-01-01

    The authors conducted a survey of university students' understanding level about words related to nuclear power before and after Fukushima Daiichi Power Plant accident, and analyzed the difference between before and after the accident. The results show that university students' understanding level improved after the accident, especially in the case of reported words by mass media. Understanding level of some nuclear power security words which were not reported so much by mass media also improved. That may be caused by rising of people's concern about nuclear power generation after the accident, and there is a possibility that the accident motivated people to access such words via internet, journals, etc. (author)

  7. Answers to your questions on high-level nuclear waste

    International Nuclear Information System (INIS)

    1987-11-01

    This booklet contains answers to frequently asked questions about high-level nuclear wastes. Written for the layperson, the document contains basic information on the hazards of radiation, the Nuclear Waste Management Program, the proposed geologic repository, the proposed monitored retrievable storage facility, risk assessment, and public participation in the program

  8. Electromagnetically induced transparency and retrieval of light pulses in a Λ-type and a V-type level scheme in Pr3+:Y2SiO5

    International Nuclear Information System (INIS)

    Beil, Fabian; Klein, Jens; Halfmann, Thomas; Nikoghosyan, Gor

    2008-01-01

    We examine electromagnetically induced transparency (EIT), the optical preparation of persistent nuclear spin coherences and the retrieval of light pulses both in a Λ-type and a V-type coupling scheme in a Pr 3+ :Y 2 SiO 5 crystal, cooled to cryogenic temperatures. The medium is prepared by optical pumping and spectral hole burning, creating a spectrally isolated Λ-type and a V-type system within the inhomogeneous bandwidth of the 3 H 4 ↔ 1 D 2 transition of the Pr 3+ ions. By EIT, in the Λ-type scheme we drive a nuclear spin coherence between the ground-state hyperfine levels, while in the V-type scheme we drive a coherence between the excited-state hyperfine levels. We observe the cancellation of absorption due to EIT and the retrieval of light pulses in both level schemes. This also permits the determination of dephasing times of the nuclear spin coherence, either in the ground state or the optically excited state

  9. Single-level resonance parameters fit nuclear cross-sections

    Science.gov (United States)

    Drawbaugh, D. W.; Gibson, G.; Miller, M.; Page, S. L.

    1970-01-01

    Least squares analyses of experimental differential cross-section data for the U-235 nucleus have yielded single level Breit-Wigner resonance parameters that fit, simultaneously, three nuclear cross sections of capture, fission, and total.

  10. Managing the high level waste nuclear regulatory commission licensing process

    International Nuclear Information System (INIS)

    Baskin, K.P.

    1992-01-01

    This paper reports that the process for obtaining Nuclear Regulatory Commission permits for the high level waste storage facility is basically the same process commercial nuclear power plants followed to obtain construction permits and operating licenses for their facilities. Therefore, the experience from licensing commercial reactors can be applied to the high level waste facility. Proper management of the licensing process will be the key to the successful project. The management of the licensing process was categorized into four areas as follows: responsibility, organization, communication and documentation. Drawing on experience from nuclear power plant licensing and basic management principles, the management requirement for successfully accomplishing the project goals are discussed

  11. Tables of nuclear level density parameters

    International Nuclear Information System (INIS)

    Chatterjee, A.; Ghosh, S.K.; Majumdar, H.

    1976-03-01

    The Renormalized Gas Model (RGM) has been used to calculate single particle level density parameters for more than 2000 nucleides over the range 9<=Z<=126 (15<=A<=338). Three separate tables present the elements on or near the valley of beta stability, neutron-rich fission fragment nucleides, and transitional nuclei, actinides and light-mass super heavy elements. Each table identifies the nucleus in terms of Z and N and presents the RGM deformation energy of binding, the total RGM structural energy correction over the free gas Fermi surface, and the level density parameter

  12. Nuclear Security Education in “non-Nuclear” Countries – Inseparable Component of Global Nuclear Security Scheme. Example of Montenegro

    International Nuclear Information System (INIS)

    Jovanovic, S.

    2014-01-01

    • Global regime of nuclear security cannot be complete and functional if all countries are not involved; • Apart from the fact that developed nuclear countries are crucial in this sense (and determining the system), due attention should be paid to small, developing, “nonnuclear” ones; • Small problems in big countries are often big problems in small countries – so it is with HRD in nuclear related fields; • Everything is based on competence, with education being fundamental for building it up; • To that aim, the role of universities is of utmost importance, while networking is another corner stone; • Experience of Montenegro, perhaps exemplary in the above context, is discussed. (author)

  13. Improving Limit Surface Search Algorithms in RAVEN Using Acceleration Schemes: Level II Milestone

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsi, Andrea [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Rabiti, Cristian [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Cogliati, Joshua Joseph [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Sen, Ramazan Sonat [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Smith, Curtis Lee [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

    2015-07-01

    The RAVEN code is becoming a comprehensive tool to perform Probabilistic Risk Assessment (PRA); Uncertainty Quantification (UQ) and Propagation; and Verification and Validation (V&V). The RAVEN code is being developed to support the Risk-Informed Safety Margin Characterization (RISMC) pathway by developing an advanced set of methodologies and algorithms for use in advanced risk analysis. The RISMC approach uses system simulator codes applied to stochastic analysis tools. The fundamental idea behind this coupling approach to perturb (by employing sampling strategies) timing and sequencing of events, internal parameters of the system codes (i.e., uncertain parameters of the physics model) and initial conditions to estimate values ranges and associated probabilities of figures of merit of interest for engineering and safety (e.g. core damage probability, etc.). This approach applied to complex systems such as nuclear power plants requires performing a series of computationally expensive simulation runs. The large computational burden is caused by the large set of (uncertain) parameters characterizing those systems. Consequently, exploring the uncertain/parametric domain, with a good level of confidence, is generally not affordable, considering the limited computational resources that are currently available. In addition, the recent tendency to develop newer tools, characterized by higher accuracy and larger computational resources (if compared with the presently used legacy codes, that have been developed decades ago), has made this issue even more compelling. In order to overcome to these limitations, the strategy for the exploration of the uncertain/parametric space needs to use at best the computational resources focusing the computational effort in those regions of the uncertain/parametric space that are “interesting” (e.g., risk-significant regions of the input space) with respect the targeted Figures Of Merit (FOM): for example, the failure of the system

  14. Integrated scheme of long-term for spent fuel management of power nuclear reactors

    International Nuclear Information System (INIS)

    Ramirez S, J. R.; Palacios H, J. C.; Martinez C, E.

    2015-09-01

    After of irradiation of the nuclear fuel in the reactor core, is necessary to store it for their cooling in the fuel pools of the reactor. This is the first step in a processes series before the fuel can reach its final destination. Until now there are two options that are most commonly accepted for the end of the nuclear fuel cycle, one is the open nuclear fuel cycle, requiring a deep geological repository for the fuel final disposal. The other option is the fuel reprocessing to extract the plutonium and uranium as valuable materials that remaining in the spent fuel. In this study the alternatives for the final part of the fuel cycle, which involves the recycling of plutonium and the minor actinides in the same reactor that generated them are shown. The results shown that this is possible in a thermal reactor and that there are significant reductions in actinides if they are recycled into reactor fuel. (Author)

  15. Systematics of nuclear mass and level density formulas

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Hisashi [Fuji Electric Co. Ltd., Kawasaki, Kanagawa (Japan)

    1998-03-01

    The phenomenological models of the nuclear mass and level density are close related to each other, the nuclear ground and excited state properties are described by using the parameter systematics on the mass and level density formulas. The main aim of this work is to provide in an analytical framework the improved energy dependent shell, pairing and deformation corrections generalized to the collective enhancement factors, which offer a systematic prescription over a great number of nuclear reaction cross sections. The new formulas are shown to be in close agreement with not only the empirical nuclear mass data but the measured slow neutron resonance spacings, and experimental systematics observed in the excitation energy dependent properties. (author)

  16. Examination of State-Level Nuclear Security Evaluation Methods

    International Nuclear Information System (INIS)

    Kim, Chan Kim; Yim, Man-Sung

    2015-01-01

    An effective global system for nuclear materials security needs to cover all materials, employing international standards and best practices, to reduce risks by reducing weapons-usable nuclear material stocks and the number of locations where they are found. Such a system must also encourage states to accept peer reviews by outside experts in order to demonstrate that effective security is in place. It is thus critically important to perform state-level evaluation of nuclear security based on an integrative framework of risk assessment. Such evaluation provides a basis of measuring the level and progress of international effort to secure and control all nuclear materials. sensitivity test by differentiating weight factors of each of the indicators and categories will be performed in the future as well

  17. An approach for determining the acceptable levels of nuclear risk

    International Nuclear Information System (INIS)

    1978-03-01

    The objective of this study was to develop a methodology for determining the acceptable levels of risk with respect to nuclear energy. It was concluded that the Atomic Energy Control Board should identify the interest groups that affect its choice of an acceptable level of risk, determine their expectations, and balance the expectations of the various groups such that the resulting acceptable level of risk is still acceptable to the Board. This would be done by interviewing experts on the subject of nuclear safety, developing and pretesting a public questionnaire, and surveying the public on acceptable cost-risk combinations

  18. Technology readiness levels for advanced nuclear fuels and materials development

    Energy Technology Data Exchange (ETDEWEB)

    Carmack, W.J., E-mail: jon.carmack@inl.gov [Idaho National Laboratory, Idaho Falls, ID (United States); Braase, L.A.; Wigeland, R.A. [Idaho National Laboratory, Idaho Falls, ID (United States); Todosow, M. [Brookhaven National Laboratory, Upton, NY (United States)

    2017-03-15

    Highlights: • Definition of nuclear fuels system technology readiness level. • Identification of evaluation criteria for nuclear fuel system TRLs. • Application of TRLs to fuel systems. - Abstract: The Technology Readiness process quantitatively assesses the maturity of a given technology. The National Aeronautics and Space Administration (NASA) pioneered the process in the 1980s to inform the development and deployment of new systems for space applications. The process was subsequently adopted by the Department of Defense (DoD) to develop and deploy new technology and systems for defense applications. It was also adopted by the Department of Energy (DOE) to evaluate the maturity of new technologies in major construction projects. Advanced nuclear fuels and materials development is needed to improve the performance and safety of current and advanced reactors, and ultimately close the nuclear fuel cycle. Because deployment of new nuclear fuel forms requires a lengthy and expensive research, development, and demonstration program, applying the assessment process to advanced fuel development is useful as a management, communication, and tracking tool. This article provides definition of technology readiness levels (TRLs) for nuclear fuel technology as well as selected examples regarding the methods by which TRLs are currently used to assess the maturity of nuclear fuels and materials under development in the DOE Fuel Cycle Research and Development (FCRD) Program within the Advanced Fuels Campaign (AFC).

  19. Effect of vibrational states on nuclear level density

    International Nuclear Information System (INIS)

    Plujko, V. A.; Gorbachenko, O. M.

    2007-01-01

    Simple methods to calculate a vibrational enhancement factor of a nuclear level density with allowance for damping of collective state are considered. The results of the phenomenological approach and the microscopic quasiparticle-phonon model are compared. The practical method of calculation of a vibrational enhancement factor and level density parameters is recommended

  20. Bit-level quantum color image encryption scheme with quantum cross-exchange operation and hyper-chaotic system

    Science.gov (United States)

    Zhou, Nanrun; Chen, Weiwei; Yan, Xinyu; Wang, Yunqian

    2018-06-01

    In order to obtain higher encryption efficiency, a bit-level quantum color image encryption scheme by exploiting quantum cross-exchange operation and a 5D hyper-chaotic system is designed. Additionally, to enhance the scrambling effect, the quantum channel swapping operation is employed to swap the gray values of corresponding pixels. The proposed color image encryption algorithm has larger key space and higher security since the 5D hyper-chaotic system has more complex dynamic behavior, better randomness and unpredictability than those based on low-dimensional hyper-chaotic systems. Simulations and theoretical analyses demonstrate that the presented bit-level quantum color image encryption scheme outperforms its classical counterparts in efficiency and security.

  1. A Prediction Packetizing Scheme for Reducing Channel Traffic in Transaction-Level Hardware/Software Co-Emulation

    OpenAIRE

    Lee , Jae-Gon; Chung , Moo-Kyoung; Ahn , Ki-Yong; Lee , Sang-Heon; Kyung , Chong-Min

    2005-01-01

    Submitted on behalf of EDAA (http://www.edaa.com/); International audience; This paper presents a scheme for efficient channel usage between simulator and accelerator where the accelerator models some RTL sub-blocks in the accelerator-based hardware/software co-simulation while the simulator runs transaction-level model of the remaining part of the whole chip being verified. With conventional simulation accelerator, evaluations of simulator and accelerator alternate at every valid simulation ...

  2. Level and decay schemes of even-A Se and Ge isotopes from (n,n'γ) reaction studies

    Energy Technology Data Exchange (ETDEWEB)

    Sigaud, J.; Patin, Y.; McEllistrem, M. T.; Haouat, G.; Lachkar, J.

    1975-06-01

    The energy levels and the decay schemes of {sup 76}Se, {sup 78}Se, {sup 80}Se, {sup 82}Se and {sup 76}Ge have been studied through the measurements of (n,n'γ) differential cross sections. Gamma-ray excitation functions have been measured between 2.0- and 4.1-MeV incident neutron energy, and angular distribution have been observed for all of these isotopes.

  3. Development of scheme for predicting atmospheric dispersion of radionuclides during nuclear emergency by using atmospheric dynamic model

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, Haruyasu; Chino, Masamichi; Yamazawa, Hiromi (Japan Atomic Energy Research Inst., Tokyo (Japan))

    1999-07-01

    The meteorological forecast models are critically important for the accuracy of predicting the atmospheric dispersion of radionuclides discharged into atmosphere during nuclear emergencies. Thus, this paper describes a new scheme for predicting environmental impacts due to accidental release of radionuclides by using an atmospheric dynamic model PHYSIC. The advantages of introducing PHYSIC are, (1) three-dimensional local meteorological forecasts can be conducted, (2) synoptic meteorological changes can be considered by inputting grid data of synoptic forecasts from Japan Meteorological Agency to PHYSIC as initial and boundary conditions, (3) forecasts can be improved by nudging method using local meteorological observations, and (4) atmospheric dispersion model can consider the variation of the mixed layer. (author)

  4. Development of scheme for predicting atmospheric dispersion of radionuclides during nuclear emergency by using atmospheric dynamic model

    International Nuclear Information System (INIS)

    Nagai, Haruyasu; Chino, Masamichi; Yamazawa, Hiromi

    1999-01-01

    The meteorological forecast models are critically important for the accuracy of predicting the atmospheric dispersion of radionuclides discharged into atmosphere during nuclear emergencies. Thus, this paper describes a new scheme for predicting environmental impacts due to accidental release of radionuclides by using an atmospheric dynamic model PHYSIC. The advantages of introducing PHYSIC are, (1) three-dimensional local meteorological forecasts can be conducted, (2) synoptic meteorological changes can be considered by inputting grid data of synoptic forecasts from Japan Meteorological Agency to PHYSIC as initial and boundary conditions, (3) forecasts can be improved by nudging method using local meteorological observations, and (4) atmospheric dispersion model can consider the variation of the mixed layer. (author)

  5. Carrier-based modulation schemes for various three-level matrix converters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, P.C.; Rong, R.C.

    2008-01-01

    different performance merits. To avoid confusion and hence fasten the converter applications in the industry, it would surely be better for modulation schemes to be developed from a common set of modulation principles that unfortunately has not yet been thoroughly defined. Contributing to that area...... a limited set of switching vectors because of its lower semiconductor count. Through simulation and experimental testing, all the evaluated matrix converters are shown to produce satisfactory sinusoidal input and output quantities using the same set of generic modulation principles, which can conveniently...

  6. Propagation of frequency-chirped laser pulses in a medium of atoms with a Λ-level scheme

    International Nuclear Information System (INIS)

    Demeter, G.; Dzsotjan, D.; Djotyan, G. P.

    2007-01-01

    We study the propagation of frequency-chirped laser pulses in optically thick media. We consider a medium of atoms with a Λ level-scheme (Lambda atoms) and also, for comparison, a medium of two-level atoms. Frequency-chirped laser pulses that induce adiabatic population transfer between the atomic levels are considered. They induce transitions between the two lower (metastable) levels of the Λ-atoms and between the ground and excited states of the two-level atoms. We show that associated with this adiabatic population transfer in Λ-atoms, there is a regime of enhanced transparency of the medium--the pulses are distorted much less than in the medium of two-level atoms and retain their ability to transfer the atomic population much longer during propagation

  7. Management of the high-level nuclear power facilities

    International Nuclear Information System (INIS)

    Preda, Marin

    2003-05-01

    This thesis approaches current issues in the management of the high power nuclear facilities and as such it appears to be important particularly for nuclear power plant operation topics. Of special interest are the failure events entailing possible catastrophic situations. The contents is structured onto ten chapters. The first chapter describes the operation regimes of the nuclear high power facilities. Highlighted here are the thesis scope and the original features of the work. The second chapter deals with operational policies developed in order to ensure the preventive maintenance of the nuclear installations. Also managing structures are described devoted to practical warranting the equipment safety function of non-classical power stations. In the third chapter cases of nuclear accidents are analyzed especially stressing the probabilistic risk and the operation regimes having in view the elimination of catastrophic events. In the fourth and fifth chapters the control of nuclear radiation emission is treated focusing the quality issue of nuclear installations required to avoid hazardous effects at level of nuclear reactor operation stage. At the same time set of operational measures is given here for preventing risks, catastrophes and chaotic situations. The chapter five presents both theoretical and practical approaches of the nuclear reactor core management concerning particularly the fuel testing, the water primary system and the quality of the involved equipment. In the sixth and seventh chapters issues of risk-quality correlations are approached as well as the structure of expert systems for monitoring the operational regimes of nuclear facilities. The efficiency of the power systems with nuclear injection is discussed and some original ideas developed in this work are evidenced in the eighth and ninth chapters. Presented are here both the operational principles and models of raising the efficiency of the interconnected nuclear stations and prices' policy

  8. Nuclear level density parameter 's dependence on angular momentum

    International Nuclear Information System (INIS)

    Aggarwal, Mamta; Kailas, S.

    2009-01-01

    Nuclear level densities represent a very important ingredient in the statistical Model calculations of nuclear reaction cross sections and help to understand the microscopic features of the excited nuclei. Most of the earlier experimental nuclear level density measurements are confined to low excitation energy and low spin region. A recent experimental investigation of nuclear level densities in high excitation energy and angular momentum domain with some interesting results on inverse level density parameter's dependence on angular momentum in the region around Z=50 has motivated us to study and analyse these experimental results in a microscopic theoretical framework. In the experiment, heavy ion fusion reactions are used to populate the excited and rotating nuclei and measured the α particle evaporation spectra in coincidence with ray multiplicity. Residual nuclei are in the range of Z R 48-55 with excitation energy range 30 to 40 MeV and angular momentum in 10 to 25. The inverse level density parameter K is found to be in the range of 9.0 - 10.5 with some exceptions

  9. Missing and Spurious Level Corrections for Nuclear Resonances

    International Nuclear Information System (INIS)

    Mitchell, G E; Agvaanluvsan, U; Pato, M P; Shriner, J F

    2005-01-01

    Neutron and proton resonances provide detailed level density information. However, due to experimental limitations, some levels are missed and some are assigned incorrect quantum numbers. The standard method to correct for missing levels uses the experimental widths and the Porter-Thomas distribution. Analysis of the spacing distribution provides an independent determination of the fraction of missing levels. We have derived a general expression for such an imperfect spacing distribution using the maximum entropy principle and applied it to a variety of nuclear resonance data. The problem of spurious levels has not been extensively addressed

  10. Nuclear level repulsion, order vs. chaos and conserved quantum numbers

    International Nuclear Information System (INIS)

    Garrett, J.D.

    1995-01-01

    A statistical analysis of the distribution of level spacings for states with the same angular momentum and parity is described in which the average spacing is calculated for the total ensemble. Though the resulting distribution of level spacings for states of deformed nuclei with Z = 62-75 and A = 155-185 is the closest to that of a Poisson distribution yet obtained for nuclear levels, significant deviations are observed for small level spacings. Many, but not all, of the very closely-spaced levels have K-values differing by several units. (orig.)

  11. Multi-model predictive control method for nuclear steam generator water level

    International Nuclear Information System (INIS)

    Hu Ke; Yuan Jingqi

    2008-01-01

    The dynamics of a nuclear steam generator (SG) is very different according to the power levels and changes as time goes on. Therefore, it is an intractable as well as challenging task to improve the water level control system of the SG. In this paper, a robust model predictive control (RMPC) method is developed for the level control problem. Based on a multi-model framework, a combination of a local nominal model with a polytopic uncertain linear parameter varying (LPV) model is built to approximate the system's non-linear behavior. The optimization problem solved here is based on a receding horizon scheme involving the linear matrix inequality (LMI) technique. Closed loop stability and constraints satisfaction in the entire operating range are guaranteed by the feasibility of the optimization problem. Finally, simulation results show the effectiveness and the good performance of the proposed method

  12. Development and validation of calculation schemes dedicated to the interpretation of small reactivity effects for nuclear data improvement

    International Nuclear Information System (INIS)

    Gruel, A.

    2011-01-01

    Reactivity measurements by the oscillation technique, as those performed in the Minerve reactor, enable to access various neutronic parameters on materials, fuels or specific isotopes. Usually, expected reactivity effects are small, about ten pcm at maximum. Then, the modeling of these experiments should be very precise, to obtain reliable feedback on the pointed parameters. Especially, calculation biases should be precisely identified, quantified and reduced to get precise information on nuclear data. The goal of this thesis is to develop a reference calculation scheme, with well quantified uncertainties, for in-pile oscillation experiments. In this work are presented several small reactivity calculation methods, based on deterministic and/or stochastic calculation codes. Those method are compared thanks to a numerical benchmark, against a reference calculation. Three applications of these methods are presented here: a purely deterministic calculation with exact perturbation theory formalism is used for the experimental validation of fission product cross sections, in the frame of reactivity loss studies for irradiated fuel; an hybrid method, based on a stochastic calculation and the exact perturbation theory is used for the readjustment of nuclear data, here 241 Am; and a third method, based on a perturbative Monte Carlo calculation, is used in a conception study. (author) [fr

  13. Scheme for generation of fully-coherent, TW power level hard X-ray pulses from baseline undulators at the European X-ray FEL

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2010-07-01

    The most promising way to increase the output power of an X-ray FEL (XFEL) is by tapering the magnetic field of the undulator. Also, significant increase in power is achievable by starting the FEL process from a monochromatic seed rather than from noise. This report proposes to make use of a cascade self-seeding scheme with wake monochromators in a tunable-gap baseline undulator at the European XFEL to create a source capable of delivering coherent radiation of unprecedented characteristics at hard X-ray wavelengths. Compared with SASE X-ray FEL parameters, the radiation from the new source has three truly unique aspects: complete longitudinal and transverse coherence, and a peak brightness three orders of magnitude higher than what is presently available at LCLS. Additionally, the new source will generate hard X-ray beam at extraordinary peak (TW) and average (kW) power level. The proposed source can thus revolutionize fields like single biomolecule imaging, inelastic scattering and nuclear resonant scattering. The self-seeding scheme with the wake monochromator is extremely compact, and takes almost no cost and time to be implemented. The upgrade proposed in this paper could take place during the commissioning stage of the European XFEL, opening a vast new range of applications from the very beginning of operations.We present feasibility study and examplifications for the SASE2 line of the European XFEL. (orig.)

  14. Energy-level scheme and transition probabilities of Si-like ions

    International Nuclear Information System (INIS)

    Huang, K.N.

    1984-01-01

    Theoretical energy levels and transition probabilities are presented for 27 low-lying levels of silicon-like ions from Z = 15 to Z = 106. The multiconfiguration Dirac-Fock technique is used to calculate energy levels and wave functions. The Breit interaction and Lamb shift contributions are calculated perturbatively as corrections to the Dirac-Fock energy. The M1 and E2 transitions between the first nine levels and the E1 transitions between excited and the ground levels are presented

  15. Fusion-Fission Transmutation Scheme-Efficient destruction of nuclear waste

    International Nuclear Information System (INIS)

    Kotschenreuther, M.; Valanju, P.M.; Mahajan, S.M.; Schneider, E.A.

    2009-01-01

    A fusion-assisted transmutation system for the destruction of transuranic nuclear waste is developed by combining a subcritical fusion-fission hybrid assembly uniquely equipped to burn the worst thermal nonfissile transuranic isotopes with a new fuel cycle that uses cheaper light water reactors for most of the transmutation. The center piece of this fuel cycle, the high power density compact fusion neutron source (100 MW, outer radius <3 m), is made possible by a new divertor with a heat-handling capacity five times that of the standard alternative. The number of hybrids needed to destroy a given amount of waste is an order of magnitude below the corresponding number of critical fast-spectrum reactors (FRs) as the latter cannot fully exploit the new fuel cycle. Also, the time needed for 99% transuranic waste destruction reduces from centuries (with FR) to decades

  16. Brief of the joint research with universities, etc. for 2002. Except the research by the JNC cooperative research scheme on the nuclear fuel cycle

    International Nuclear Information System (INIS)

    2003-09-01

    The Japan Nuclear Cycle Development Institute (JNC) promote the basic and fundamental research in relation to the research and development projects of JNC through collaboration with universities and other research institutes (referred to as 'universities, etc.' below). This report includes a summary of the results of the research carried out in fiscal year 2002 on 15 joint researches with universities, etc. In addition, this report removes the research by the JNC Cooperative Research Scheme on the Nuclear Fuel Cycle. (author)

  17. Table of Half-Lives for Excited Nuclear Levels

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1970-07-15

    The knowledge of the half-lives of excited states is often a valuable information in the investigation of the nuclear level structure. The present paper contains a collection of such half-lives being published in the current literature over the period 1967-1970. The data is arranged in increasing order of mass number.

  18. Low-level waste management at the Nuclear Research Center

    International Nuclear Information System (INIS)

    Montanez, O.; Blanco, D.; Vallarino, V.; Calisto, W.

    1986-01-01

    A general overview of low-level radioactive waste management at the Nuclear Investigation Centre (CIN) of Uruguay is presented. The CIN is a pilot centre of research and development of techniques for implementing measurements for radioactive waste storage and control. (M.C.K.) [pt

  19. Asynchronous Two-Level Checkpointing Scheme for Large-Scale Adjoints in the Spectral-Element Solver Nek5000

    Energy Technology Data Exchange (ETDEWEB)

    Schanen, Michel; Marin, Oana; Zhang, Hong; Anitescu, Mihai

    2016-01-01

    Adjoints are an important computational tool for large-scale sensitivity evaluation, uncertainty quantification, and derivative-based optimization. An essential component of their performance is the storage/recomputation balance in which efficient checkpointing methods play a key role. We introduce a novel asynchronous two-level adjoint checkpointing scheme for multistep numerical time discretizations targeted at large-scale numerical simulations. The checkpointing scheme combines bandwidth-limited disk checkpointing and binomial memory checkpointing. Based on assumptions about the target petascale systems, which we later demonstrate to be realistic on the IBM Blue Gene/Q system Mira, we create a model of the expected performance of our checkpointing approach and validate it using the highly scalable Navier-Stokes spectralelement solver Nek5000 on small to moderate subsystems of the Mira supercomputer. In turn, this allows us to predict optimal algorithmic choices when using all of Mira. We also demonstrate that two-level checkpointing is significantly superior to single-level checkpointing when adjoining a large number of time integration steps. To our knowledge, this is the first time two-level checkpointing had been designed, implemented, tuned, and demonstrated on fluid dynamics codes at large scale of 50k+ cores.

  20. Development of a new electron-RI colliding scheme for study of unstable nuclear structure

    International Nuclear Information System (INIS)

    Wakasugi, M.; Emoto, T.; Ishihara, M.; Koseki, T.; Ohnishi, T.; Suda, T.; Takeda, H.; Yano, Y.; Kurita, K.

    2004-01-01

    A new method of electron scattering experiment for unstable nuclei is proposed. In this method, the low energy ion beam is injected into the electron storage ring where the transverse potential well made by electron beam exists. The ion beam is three-dimensionally confined by applying longitudinal static mirror potential externally. The ion beam confined on the electron beam axis is regarded as the Self-Confining Radioactive Ion Target (SCRIPT). This idea originally comes from the ion trap phenomenon of the electron storage ring. For the electron scattering experiment, luminosity higher than 10 26 s -1 cm -2 is required for heavy nuclei. In order to test this idea, computer simulation is performed. Limit of the storage of positive charges, change of the ion valences caused by the collisions with the electrons, nuclear decays and capture of residual gas, other interactions and the luminosity are investigated. Demonstration of this idea is under way at the KSR storage ring of Kyoto University with the SCRIPT instrument equipped with forty built-in electrodes. It is expected that the number of ions accumulated and the luminosity of the collisions are about 10 6 and 2x10 25 s -1 cm -2 , respectively, at the electron beam energy of 100 MeV and current of 100 mA(max). (S. Funahashi)

  1. Cooperative control scheme for an HVDC system connected to an isolated BWR nuclear power plant

    International Nuclear Information System (INIS)

    Sakurai, T.; Goto, K.; Kawai, T.; Matori, I.; Nakao, T.; Watanabe, A.

    1983-01-01

    This paper describes a cooperative control system to achieve stable operation of an isolated BWR nuclear plant linked to an HVDC system. In the proposed control system, under normal conditions the power plant is controlled according to the generating power reference and the generator frequency deviation is adjusted by converter power control. Such frequency control is also effective in the case of AC-DC system faults. In addition to the frequency control, an overload control is provided with the HVDC system, where the DC transmission power in the sound poles is increased due to a fault detection signal from the faulty pole. Effects of the above mentioned control systems were studied using digital dynamic programs. The sets of simulation results confirmed that in the case of a DC single pole fault, the plant is able to continue operation without any use of the turbine speed control units even for a restarting failure in the faulty pole. In case of a DC two pole fault, the plant is able to continue operation, being assisted by turbine speed control units when restarting in the faulty poles succeeds. In case of an AC three-line to ground fault near the AC terminal of the converter at the sending or receiving end, the system is able to continue stable operation, being supplemented by the turbine control unit when the faulty section of the AC system is isolated by a main or back-up relaying system

  2. Comparison between different computational schemes for variational calculations in nuclear structure

    International Nuclear Information System (INIS)

    Puddu, G.

    2009-01-01

    We compare several iteration methods for angular-momentum- and parity-projected Hartree-Fock calculations. We used the Anderson update, the modified Broyden method, newly introduced in nuclear-structure calculations, and variants of the Broyden-Fletcher-Goldhaber-Shanno methods (BFGS). We performed ground-state calculations for 18 C and 6 Li using the two-body Hamiltonian obtained from the CDBonn-2000 potential via the Lee-Suzuki renormalization method. We found that BFGS methods are superior to both the Anderson update and to the modified Broyden method. In the case of 6 Li we found that the Anderson update and modified Broyden method do not converge to the angular-momentum- and parity-projected Hartree-Fock minimum. The reason is traced back to the lack of a mechanism that guarantees a decrease of the energy from one iteration to the next and to the fact that these methods guarantee a stationary solution rather than a minimum of the energy. (orig.)

  3. High-level nuclear waste disposal: Ethical considerations

    International Nuclear Information System (INIS)

    Maxey, M.N.

    1985-01-01

    Popular skepticism about, and moral objections to, recent legislation providing for the management and permanent disposal of high-level radioactive wastes have derived their credibility from two major sources: government procrastination in enacting waste disposal program, reinforcing public perceptions of their unprecedented danger and the inflated rhetoric and pretensions to professional omnicompetence of influential scientists with nuclear expertise. Ethical considerations not only can but must provide a mediating framework for the resolution of such a polarized political controversy. Implicit in moral objections to proposals for permanent nuclear waste disposal are concerns about three ethical principles: fairness to individuals, equitable protection among diverse social groups, and informed consent through due process and participation

  4. University-level education in nuclear and radiochemistry in Slovenia

    International Nuclear Information System (INIS)

    Smodis, B.

    2006-01-01

    The status of education in nuclear and radiochemistry in Slovenia is reviewed and elucidated at both undergraduate and graduate levels. It is observed that both the quantity and the quality of studies have deteriorated during recent years/decades, thus following similar trends in the developed countries. Presently, no dedicated study of radioactivity is offered within the country. The main reason for this deterioration is a general decline of interest for studying nuclear sciences and the limited need for such specialization in a small country such as Slovenia. (author)

  5. Nuclear level density variation with angular momentum induced shape transition

    International Nuclear Information System (INIS)

    Aggarwal, Mamta

    2016-01-01

    Variation of Nuclear level density (NLD) with the excitation energy and angular momentum in particular has been a topic of interest in the recent past and there have been continuous efforts in this direction on the theoretical and experimental fronts but a conclusive trend in the variation of nuclear level density parameter with angular momentum has not been achieved so far. A comprehensive investigation of N=68 isotones around the compound nucleus 119 Sb from neutron rich 112 Ru (Z=44) to neutron deficient 127 Pr (Z= 59) nuclei is presented to understand the angular momentum induced variations in inverse level density parameter and the possible influence of deformation and structural transitions on the variations on NLd

  6. Seismic fragility levels of nuclear power plant equipment

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1987-01-01

    Seismic fragility levels of safety-related electrical and mechanical equipment used in nuclear power plants are discussed. The fragility level is defined as the vibration level corresponding to initiation of equipment malfunctions. The test response spectrum is used as a measure of this vibration level. The fragility phenomenon of an equipment is represented by a number of response spectra corresponding to various failure modes. Analysis methods are described for determination of the fragility level by use of existing test data. Useful conversion factors are tabulated to transform test response spectra from one damping value to another. Results are presented for switch-gears and motor control centers. The capacity levels of these equipment assemblies are observed to be limited by malfunctioning of contactors, motor starters, relays and/or switches. The applicability of the fragility levels, determined in terms of test response spectra, to Seismic Margin Studies and Probabilistic Risk Assessments is discussed and specific recommendations are provided

  7. Environmental radioactivity levels, Browns Ferry Nuclear Plant: Annual report, 1986

    International Nuclear Information System (INIS)

    1986-04-01

    The report presents data gathered during radiological monitoring program conducted in the environs of the Browns Ferry Nuclear Plant. Dose estimates were made from concentrations of radioactivity found in samples of media including air, milk, food products, drinking water, and fish. Inhalation and ingestion doses estimated for persons at the indicator locations were essentially identical to those determined for persons at control locations. Greater than 95% of those doses were contributed by the naturally occurring K-40 and by Sr-90 and Cs-137 which are long-lived radioisotopes found in fallout from nuclear weapons testing. Increased levels of I-131 were reported in air, milk, and rainwater following the accident at the Chernobyl nuclear power station. In addition, Ru-103, Cs-137, and Cs-134 were identified in air particulates, and traces of Ru-103 were found in rainwater

  8. Natural Assurance Scheme: A level playing field framework for Green-Grey infrastructure development.

    Science.gov (United States)

    Denjean, Benjamin; Altamirano, Mónica A; Graveline, Nina; Giordano, Raffaele; van der Keur, Peter; Moncoulon, David; Weinberg, Josh; Máñez Costa, María; Kozinc, Zdravko; Mulligan, Mark; Pengal, Polona; Matthews, John; van Cauwenbergh, Nora; López Gunn, Elena; Bresch, David N

    2017-11-01

    This paper proposes a conceptual framework to systematize the use of Nature-based solutions (NBS) by integrating their resilience potential into Natural Assurance Scheme (NAS), focusing on insurance value as corner stone for both awareness-raising and valuation. As such one of its core goal is to align research and pilot projects with infrastructure development constraints and priorities. Under NAS, the integrated contribution of natural infrastructure to Disaster Risk Reduction is valued in the context of an identified growing need for climate robust infrastructure. The potential of NAS benefits and trade-off are explored by through the alternative lens of Disaster Resilience Enhancement (DRE). Such a system requires a joint effort of specific knowledge transfer from research groups and stakeholders to potential future NAS developers and investors. We therefore match the knowledge gaps with operational stages of the development of NAS from a project designer perspective. We start by highlighting the key role of the insurance industry in incentivizing and assessing disaster and slow onset resilience enhancement strategies. In parallel we place the public sector as potential kick-starters in DRE initiatives through the existing initiatives and constraints of infrastructure procurement. Under this perspective the paper explores the required alignment of Integrated Water resources planning and Public investment systems. Ultimately this will provide the possibility for both planners and investors to design no regret NBS and mixed Grey-Green infrastructures systems. As resources and constraints are widely different between infrastructure development contexts, the framework does not provide explicit methodological choices but presents current limits of knowledge and know-how. In conclusion the paper underlines the potential of NAS to ease the infrastructure gap in water globally by stressing the advantages of investment in the protection, enhancement and restoration of

  9. Float level switch for a nuclear power plant containment vessel

    International Nuclear Information System (INIS)

    Powell, J.G.

    1993-01-01

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures

  10. Float level switch for a nuclear power plant containment vessel

    Science.gov (United States)

    Powell, James G.

    1993-01-01

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.

  11. Coherence modulation at the photon-counting level: A new scheme for secure communication

    International Nuclear Information System (INIS)

    Rhodes, William T; Boughanmi, Abdellatif; Moreno, Yezid Torres

    2016-01-01

    When operated at the photon-counting level, coherence modulation can provide quantifiably secure binary signal transmission between two entities, security being based on the nonclonability of photons. (paper)

  12. PNGMDR 2013-2015. Industrial scheme for very-low-level waste management

    International Nuclear Information System (INIS)

    2015-08-01

    The objectives of this document are to recall quantitative and qualitative situations of the very-low-level waste management sector, to consolidate production perspectives for producers, to make an inventory of possibilities of extension and optimisation of industrial capacities of the sector, to define priorities for the different envisaged optimisation options, and to describe the organisation for the follow-up of action progress. After a brief presentation of the context, it presents the French very-low-level waste sector which is specific to the French context, outlines the main challenges for the industrial very-low-level waste management sector, indicates current projects of assessment for the sector, reports an analysis of the relevance of the different envisaged volume optimisation ways, briefly presents different scenarios, gives a brief overview of examples of very-low-level waste management in other countries, and finally states some proposals

  13. Level repulsion, nuclear chaos, and conserved quantum numbers

    International Nuclear Information System (INIS)

    Garrett, J.D.

    1993-01-01

    A statistical analysis of the distribution of level spacings for states with the same spin and parity is described in which the average spacing is calculated for the total ensemble. Though the resulting distribution of level spacings for states of deformed nuclei with Z = 62 - 75 and A = 155 - 185 is the closest to that of a Poisson distribution yet obtained for nuclear levels, significant deviations are observed for small level spacings. Many, but not all, of the very closely-spaced levels have K-values differing by several units. The analysis of level spacings in 157 Ho indicate that considerable caution should be excerised when drawing conclusions from such an analysis for a single deformed nucleus, since the sizable number of spacings that can be obtained from a few rotational bands are not all independent

  14. Using an Ecosystem Approach to complement protection schemes based on organism-level endpoints

    International Nuclear Information System (INIS)

    Bradshaw, Clare; Kapustka, Lawrence; Barnthouse, Lawrence; Brown, Justin; Ciffroy, Philippe; Forbes, Valery; Geras'kin, Stanislav; Kautsky, Ulrik; Bréchignac, François

    2014-01-01

    Radiation protection goals for ecological resources are focussed on ecological structures and functions at population-, community-, and ecosystem-levels. The current approach to radiation safety for non-human biota relies on organism-level endpoints, and as such is not aligned with the stated overarching protection goals of international agencies. Exposure to stressors can trigger non-linear changes in ecosystem structure and function that cannot be predicted from effects on individual organisms. From the ecological sciences, we know that important interactive dynamics related to such emergent properties determine the flows of goods and services in ecological systems that human societies rely upon. A previous Task Group of the IUR (International Union of Radioecology) has presented the rationale for adding an Ecosystem Approach to the suite of tools available to manage radiation safety. In this paper, we summarize the arguments for an Ecosystem Approach and identify next steps and challenges ahead pertaining to developing and implementing a practical Ecosystem Approach to complement organism-level endpoints currently used in radiation safety. - Highlights: • An Ecosystem Approach to radiation safety complements the organism-level approach. • Emergent properties in ecosystems are not captured by organism-level endpoints. • The proposed Ecosystem Approach better aligns with management goals. • Practical guidance with respect to system-level endpoints is needed. • Guidance on computational model selection would benefit an Ecosystem Approach

  15. Face-iris multimodal biometric scheme based on feature level fusion

    Science.gov (United States)

    Huo, Guang; Liu, Yuanning; Zhu, Xiaodong; Dong, Hongxing; He, Fei

    2015-11-01

    Unlike score level fusion, feature level fusion demands all the features extracted from unimodal traits with high distinguishability, as well as homogeneity and compatibility, which is difficult to achieve. Therefore, most multimodal biometric research focuses on score level fusion, whereas few investigate feature level fusion. We propose a face-iris recognition method based on feature level fusion. We build a special two-dimensional-Gabor filter bank to extract local texture features from face and iris images, and then transform them by histogram statistics into an energy-orientation variance histogram feature with lower dimensions and higher distinguishability. Finally, through a fusion-recognition strategy based on principal components analysis and support vector machine (FRSPS), feature level fusion and one-to-n identification are accomplished. The experimental results demonstrate that this method can not only effectively extract face and iris features but also provide higher recognition accuracy. Compared with some state-of-the-art fusion methods, the proposed method has a significant performance advantage.

  16. Chemical digestion of low level nuclear solid waste material

    International Nuclear Information System (INIS)

    Cooley, C.R.; Lerch, R.E.

    1976-01-01

    A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230 0 --300 0 C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue. 6 claims, no drawings

  17. Nuclear Accidents Intervention Levels for Protection of the Public

    International Nuclear Information System (INIS)

    1989-01-01

    The impact of the 1986 Chernobyl accident called attention to the need to improve international harmonization of the principles and criteria for the protection of the public in the event of a nuclear accident. This report provides observations and guidance related to the harmonization of radiological protection criteria, and is intended to be of use to national authorities and international organizations examining the issue of emergency response planning and intervention levels

  18. Multi-domain, higher order level set scheme for 3D image segmentation on the GPU

    DEFF Research Database (Denmark)

    Sharma, Ojaswa; Zhang, Qin; Anton, François

    2010-01-01

    to evaluate level set surfaces that are $C^2$ continuous, but are slow due to high computational burden. In this paper, we provide a higher order GPU based solver for fast and efficient segmentation of large volumetric images. We also extend the higher order method to multi-domain segmentation. Our streaming...

  19. Final disposal of high levels waste and spent nuclear fuel

    International Nuclear Information System (INIS)

    Gelin, R.

    1984-05-01

    Foreign and international activities on the final disposal of high-level waste and spent nuclear fuel have been reviewed. A considerable research effort is devoted to development of acceptable disposal options. The different technical concepts presently under study are described in the report. Numerous studies have been made in many countries of the potential risks to future generations from radioactive wastes in underground disposal repositories. In the report the safety assessment studies and existing performance criteria for geological disposal are briefly discussed. The studies that are being made in Canada, the United States, France and Switzerland are the most interesting for Sweden as these countries also are considering disposal into crystalline rocks. The overall time-tables in different countries for realisation of the final disposal are rather similar. Normally actual large-scale disposal operations for high-level wastes are not foreseen until after year 2000. In the United States the Congress recently passed the important Nuclear Waste Policy Act. It gives a rather firm timetable for site-selection and construction of nuclear waste disposal facilities. According to this act the first repository for disposal of commercial high-level waste must be in operation not later than in January 1998. (Author)

  20. Mutual influences of rated currents, short circuit levels, fault durations and integrated protective schemes for industrial distribution MV switchgears

    Energy Technology Data Exchange (ETDEWEB)

    Gaidano, G. (FIAT Engineering, Torino, Italy); Lionetto, P.F.; Pelizza, C.; Tommazzolli, F.

    1979-01-01

    This paper deals with the problem of integrated and coordinated design of distribution systems, as regards the definition of system structure and parameters together with protection criteria and schemes. Advantages in system operation, dynamic response, heavier loads with reduced machinery rating margins and overall cost reduction, can be achieved. It must be noted that MV switchgears installed in industrial main distribution substations are the vital nodes of the distribution system. Very large amounts of power (up to 100 MW and more) are conveyed through MV busbars, coming from Utility and from in-plant generators and outgoing to subdistribution substations, to step-down transformers and to main concentrated loads (big drivers, furnaces etc.). Criteria and methods already studied and applied to public distribution are examined to assess service continuity and economics by means of the reduction of thermal stresses, minimization of disturbances and improvement of system stability. The life of network components depends on sizing, on fault energy levels and on probability of fault occurrence. Constructional measures and protection schemes, which reduce probability and duration of faults, are the most important tools to improve overall reliability. The introduction of advanced techniques, mainly based on computer application, not only allows drastic reduction of fault duration, but also permits the system to operate, under any possible contingency, in the optimal conditions, as the computer provides adaptive control. This mode of system management makes it possible to size network components with reference to the true magnitude of system quantities, avoiding expensive oversizing connected to the unflexibility of conventional protection and control schemes.

  1. A SCHEME FOR TEMPLATE SECURITY AT FEATURE FUSION LEVEL IN MULTIMODAL BIOMETRIC SYSTEM

    OpenAIRE

    Arvind Selwal; Sunil Kumar Gupta; Surender Kumar

    2016-01-01

    Biometric is the science of human recognition based upon using their biological, chemical or behavioural traits. These systems are used in many real life applications simply from biometric based attendance system to providing security at very sophisticated level. A biometric system deals with raw data captured using a sensor and feature template extracted from raw image. One of the challenges being faced by designers of these systems is to secure template data extracted from the biometric mod...

  2. Angular momentum dependence of the nuclear level density parameter

    International Nuclear Information System (INIS)

    Aggarwal, Mamta; Kailas, S.

    2010-01-01

    Dependence of nuclear level density parameter on the angular momentum and temperature is investigated in a theoretical framework using the statistical theory of hot rotating nuclei. The structural effects are incorporated by including shell correction, shape, and deformation. The nuclei around Z≅50 with an excitation energy range of 30 to 40 MeV are considered. The calculations are in good agreement with the experimentally deduced inverse level density parameter values especially for 109 In, 113 Sb, 122 Te, 123 I, and 127 Cs nuclei.

  3. Low-level nuclear waste in Washington State

    International Nuclear Information System (INIS)

    Williams, H.

    1986-01-01

    A commercial disposal site for low-level nuclear wastes opened at Hanford in 1965. By 1971 a total of six were in operation: Hanford, Nevada, South Carolina, Kentucky, New York State, and Illinois. The history of the operation of these sites is described. Only the first three listed are still open. The effects of the large volumes of waste expected from Three Mile Island are described. This paper examines the case history of Hanford operations with low-level waste disposal for lessons that might apply in other states being considered for disposal sites

  4. Unified model of nuclear mass and level density formulas

    International Nuclear Information System (INIS)

    Nakamura, Hisashi

    2001-01-01

    The objective of present work is to obtain a unified description of nuclear shell, pairing and deformation effects for both ground state masses and level densities, and to find a new set of parameter systematics for both the mass and the level density formulas on the basis of a model for new single-particle state densities. In this model, an analytical expression is adopted for the anisotropic harmonic oscillator spectra, but the shell-pairing correlation are introduced in a new way. (author)

  5. Analytical theory for the nuclear level shift of hadronic atoms

    International Nuclear Information System (INIS)

    Kudryavtsev, A.E.; Lisin, V.I.; Popov, V.S.

    1982-01-01

    The spectrum problem in the Coulomb potential distorted at small distances is considered. Nuclear shifts of 3-levels in p anti p and Σ - p atoms are calculated. The probabilities of radiative transitions from p-states to the shifted s-states in hadronic atom are also given. It is shown that the reconstruction of atomic levels switches to oscillation regime when absorption increases. The limits of applicability of the perturbation theory in terms of the scattering length for different values of absorption is discussed. An exactly solvable model, Coulomb plus Yamaguchi potential, is considered

  6. Low-level nuclear waste tested for fertilizer value

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    The nuclear power industry keeps coming up with proposals for getting rid of radioactive waste - burying it deep in the ground, sinking it at sea and even sending it into space reports Common Cause magazine under a headline, The Latest in Recycling. At its Sequoyah Fuels facility in Oklahoma, Kerr-McGee manufactures fuel for nuclear power plants, generating a low-level radioactive liquid waste product called raphinate. After processing to remove radioactive substances, Kerr-McGee has gotten approval from the Nuclear Regulatory Commission to use the nitrogen-rich residue as a fertilizer - but not to market it. As a result, Kerr-McGee is reported to be buying up thousands of acres of land on which to spread raphinate. The acreage is used to grow hay, which the company has gotten an okay to sell. The recycling effort hasn't exactly won neighborhood friends for the company, noted Common Cause. According to Kerr-McGee's corporate communications direct, When you say to somebody, Sequoyah Fuels is putting nuclear waste (on farmland), people jump up a wall

  7. PSA Level 2:Scope And Method Of PSA Level 2 For Nuclear Power Plant

    International Nuclear Information System (INIS)

    Widodo, Surip; Antariksawan, Anhar R.

    2001-01-01

    A study of scope and method of PSA Level 2 had been conducted. The background of the study is the need to gain the capability to well perform PSA Level 2 for nuclear facilities. This study is a literature survey. The scope of PSA Level 2 consists of generating plant damage states, accident progression analysis, and grouping source terms. Concerning accident progression analysis, several methods are used, among others event tree method, named accident progression event tree (APET) or containment event tree (CET), and fault tree method. The end result of PSA Level 2 is release end states which is grouped into release bins. The results will be used for PSA Level 3

  8. Level Scheme of {sup 223}Fr; Estudio del esquema de niveles del {sup 223}Fr

    Energy Technology Data Exchange (ETDEWEB)

    Gaeta, R; Gonzalez, L; Roldan, C

    1972-07-01

    A study has been made of the decay of {sup 227}Ac at levels of {sub 223}Fr, means of alpha Spectrometers of Si barrier detector and gamma Spectrometers of Ge(Li). The rotational bands 1/2-(541 {down_arrow}), 1/2-(530 {up_arrow}) and 3/2-(532 {down_arrow}) have been identified, as well as two octupolar bands associated with the fundamental one. The results obtained indicate that the unified model is applicable in this intermediate zone of the nuclide chart. (Author) 150 refs.

  9. External radiation levels in installations of nuclear technology center

    International Nuclear Information System (INIS)

    Maletta, Paulo Guilherme M.; Filipetto, Joao; Wakabayashi, Tetsuaki; Silva, Teogenes A. da

    2005-01-01

    The radiological protection is a basic activity of nuclear technology center so that can carry through its activities with security, having to be planned and executed with total effectiveness. One of the basic tools of the radiological protection is the adoption of monitoring programs, that have as objective generality to evaluate the radiological conditions of the workstation and to assure that these conditions are acceptable safe for the displayed individuals, either workers or members of the public, as established in the basic norms of radiological protection. The Centro de Desenvolvimento da Tecnologia Nuclear - CDTN, first institution in Brazil, created in 1952 to entirely dedicate the related works to the nuclear area, to own 39 building, of which they are kept the Triga Reactor, Irradiation Gamma Laboratory, Reject Laboratory, Calibration Dosemeters Laboratory and others. In such installations, radioactive materials are produced, handled, processed and stored, being necessary the levels of external radiation ambient monitoring. As part of the radioprotection plan, monitoring 63 points on strategically located in the external areas to the building of CDTN, using characterized and calibrated thermoluminescence dosemeters. This work describes the dose distribution of the points, the doses evaluation procedure and the 4 results carried through between 2001 and 2004. The data demonstrate the attendance to the level of security established in the basic norm, what it contributed for the operation licensing of to the IBAMA. (author)

  10. Immobilisation of high level nuclear reactor wastes in SYNROC

    Energy Technology Data Exchange (ETDEWEB)

    Ringwood, A E; Kesson, S E; Ware, N G; Hibberson, W; Major, A [Australian National Univ., Canberra. Inst. of Advanced Studies

    1979-03-15

    It is stated that the elements occurring in high-level nuclear reactor wastes can be safely immobilised by incorporating them within the crystal lattices of the constituent minerals of a synthetic rock (SYNROC). The preferred form of SYNROC can accept up to 20% of high level waste calcine to form dilute solid solutions. The constituent minerals, or close structural analogues, have survived in a wide range of geochemical environments for periods of 20 to 2,000 Myr whilst immobilising the same elements present in nuclear wastes. SYNROC is unaffected by leaching for 24 hours in pure water or 10 wt % NaCl solution at high temperatures and pressure whereas borosilicate glasses completely decompose in a few hours in much less severe hydrothermal conditions. The combination of these leaching results with the geological evidence of long-term stability indicates that SYNROC would be vastly superior to glass in its capacity to safely immobilise nuclear wastes, when buried in a suitable geological repository. A dense, compact, mechanically strong form of SYNROC suitable for geological disposal can be produced by a process as economical as that which incorporates radioactive waste in borosilicate glasses.

  11. Phase diagram of a QED-cavity array coupled via a N-type level scheme

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Jiasen; Rossini, Davide [CNR, NEST, Scuola Normale Superiore and Istituto di Nanoscienze, Pisa (Italy); Fazio, Rosario [CNR, NEST, Scuola Normale Superiore and Istituto di Nanoscienze, Pisa (Italy); National University of Singapore, Center for Quantum Technologies, Singapore (Singapore)

    2015-01-01

    We study the zero-temperature phase diagram of a one-dimensional array of QED cavities where, besides the single-photon hopping, an additional coupling between neighboring cavities is mediated by an N-type four-level system. By varying the relative strength of the various couplings, the array is shown to exhibit a variety of quantum phases including a polaritonic Mott insulator, a density-wave and a superfluid phase. Our results have been obtained by means of numerical density-matrix renormalization group calculations. The phase diagram was obtained by analyzing the energy gaps for the polaritons, as well as through a study of two-point correlation functions. (orig.)

  12. Two-level modulation scheme to reduce latency for optical mobile fronthaul networks.

    Science.gov (United States)

    Sung, Jiun-Yu; Chow, Chi-Wai; Yeh, Chien-Hung; Chang, Gee-Kung

    2016-10-31

    A system using optical two-level orthogonal-frequency-division-multiplexing (OFDM) - amplitude-shift-keying (ASK) modulation is proposed and demonstrated to reduce the processing latency for the optical mobile fronthaul networks. At the proposed remote-radio-head (RRH), the high data rate OFDM signal does not need to be processed, but is directly launched into a high speed photodiode (HSPD) and subsequently emitted by an antenna. Only a low bandwidth PD is needed to recover the low data rate ASK control signal. Hence, it is simple and provides low-latency. Furthermore, transporting the proposed system over the already deployed optical-distribution-networks (ODNs) of passive-optical-networks (PONs) is also demonstrated with 256 ODN split-ratios.

  13. Water level control for a nuclear steam generator

    International Nuclear Information System (INIS)

    Wen Tan

    2011-01-01

    Research highlights: → A water level control system for a nuclear steam generator (SG) is proposed. → The parameters of the control system are directly related to those of the plant model thus scheduling is easy to implement in practice. → The proposed gain-scheduled controller can achieve good performance at both low and high power levels. - Abstract: A water level control system for a nuclear steam generator (SG) is proposed. The control system consists of a feedback controller and a feedforward controller. The feedback controller is of first order, the feedforward controller is of second order, and parameters of the two controllers are directly related to the parameters of plant model thus scheduling is easy to implement in practice. Robustness and performance of the feedback and the feedforward controllers are analyzed in details and tuning of the two parameters of the controllers are discussed. Comparisons among a single robust controller, a multi-model controller and a gain-scheduled controller are studied. It is shown that the proposed gain-scheduled controller can achieve good performance at both low and high power levels.

  14. Assessment of building integrated energy supply and energy saving schemes on a national level in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Muenster, M.; Morthorst, P.E.; Birkl, C.

    2011-06-15

    In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The results of these analyses were integrated in five scenarios to examine the consequences at national level of implementing insulation together with solar panels, photovoltaics and heat pumps in single-family houses. The simulations focused on the building period between 1961 and 1972 characterised by high building activity and low energy performance. The five scenarios - a baseline scenario, a maximum savings scenario, a maximum production scenario, and a combination scenario - showed that regardless of scenario, a consequent use of individual heat pumps leads to the greatest energy savings and CO{sub 2} reductions. (ln)

  15. Parity dependence of the nuclear level density at high excitation

    International Nuclear Information System (INIS)

    Rao, B.V.; Agrawal, H.M.

    1995-01-01

    The basic underlying assumption ρ(l+1, J)=ρ(l, J) in the level density function ρ(U, J, π) has been checked on the basis of high quality data available on individual resonance parameters (E 0 , Γ n , J π ) for s- and p-wave neutrons in contrast to the earlier analysis where information about p-wave resonance parameters was meagre. The missing level estimator based on the partial integration over a Porter-Thomas distribution of neutron reduced widths and the Dyson-Mehta Δ 3 statistic for the level spacing have been used to ascertain that the s- and p-wave resonance level spacings D(0) and D(1) are not in error because of spurious and missing levels. The present work does not validate the tacit assumption ρ(l+1, J)=ρ(l, J) and confirms that the level density depends upon parity at high excitation. The possible implications of the parity dependence of the level density on the results of statistical model calculations of nuclear reaction cross sections as well as on pre-compound emission have been emphasized. (orig.)

  16. Parameters affecting level measurement interpretation of nuclear fuel solutions

    International Nuclear Information System (INIS)

    Hunt, B.A.; Landat, D.A.

    1999-01-01

    This paper describes a level measurement technique commonly used in the measurement of radioactive liquids and equipment utilised by the inspectors for safeguards purposes. Some of the influencing parameters affecting the measurement results by this technique are characterised. An essential requisite for successful process operations in chemical facilities involving liquids generally require some physical measurements to be made in-line for both process and quality control in order to achieve the necessary final product specifications . In nuclear fuel reprocessing facilities, the same objectives apply coupled however with an additional requirement of achieving nuclear material accountancy and control. In view of the strategic importance of some of the process vessels in nuclear facilities, accountancy has to be supported by volume and density measurements of low uncertainty. Inspectors therefore require instruments which are at the very least as good as or better than operator's equipment. The classical measurement technique and most widely applied for process liquids in nuclear installations is the bubbler probe or dip-tube technique. Here a regulated flow of air passes through tubes inserted to various depths into the vessel and pressure readings are measured which are a function of the presence of liquid height and density of solution in the tank. These readings, taken together with a pre-determined calibration curve are sufficient for the volume and amount of liquor in a tank to be quantified. All measurement equipment and instrumentation are long distances from the tank environment. The key physical parameter to measure at this location is therefore pressure. Equipment designed developed, commissioned and tested in the tank measurement facilities at Ispra and in nuclear installations in Europe, Japan and the USA, house digital pressure transducer modules with manufacture's declared features of better than 0.01% accuracy and long term stability of 0.01% full

  17. Comparisons between a new point kernel-based scheme and the infinite plane source assumption method for radiation calculation of deposited airborne radionuclides from nuclear power plants.

    Science.gov (United States)

    Zhang, Xiaole; Efthimiou, George; Wang, Yan; Huang, Meng

    2018-04-01

    Radiation from the deposited radionuclides is indispensable information for environmental impact assessment of nuclear power plants and emergency management during nuclear accidents. Ground shine estimation is related to multiple physical processes, including atmospheric dispersion, deposition, soil and air radiation shielding. It still remains unclear that whether the normally adopted "infinite plane" source assumption for the ground shine calculation is accurate enough, especially for the area with highly heterogeneous deposition distribution near the release point. In this study, a new ground shine calculation scheme, which accounts for both the spatial deposition distribution and the properties of air and soil layers, is developed based on point kernel method. Two sets of "detector-centered" grids are proposed and optimized for both the deposition and radiation calculations to better simulate the results measured by the detectors, which will be beneficial for the applications such as source term estimation. The evaluation against the available data of Monte Carlo methods in the literature indicates that the errors of the new scheme are within 5% for the key radionuclides in nuclear accidents. The comparisons between the new scheme and "infinite plane" assumption indicate that the assumption is tenable (relative errors within 20%) for the area located 1 km away from the release source. Within 1 km range, the assumption mainly causes errors for wet deposition and the errors are independent of rain intensities. The results suggest that the new scheme should be adopted if the detectors are within 1 km from the source under the stable atmosphere (classes E and F), or the detectors are within 500 m under slightly unstable (class C) or neutral (class D) atmosphere. Otherwise, the infinite plane assumption is reasonable since the relative errors induced by this assumption are within 20%. The results here are only based on theoretical investigations. They should

  18. Global trends in nuclear education at the tertiary level

    International Nuclear Information System (INIS)

    Kemeny, L.G.

    2001-01-01

    The public perception of nuclear science and engineering and the nuclear industry is today, primarily shaped by radical greens, nuclear-opponents, the media and socio-political opportunists. Only countries with a well diversified tertiary education system embracing all aspects of nuclear science and engineering can counter efficiently the pseudo-science and socio-political manipulation which has severely restricted nuclear energy development over the past three decades. National laboratories alone find this task extremely difficult, if not impossible

  19. Technical basis for staffing levels at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Shurberg, D.A.; Haber, S.B. [Brookhaven National Lab., Upton, NY (United States); Morisseau, D. [Nuclear Regulatory Commission, Washington, DC (United States)] [and others

    1995-04-01

    The objective of this project is to provide a technical basis for the establishment of criteria for minimum staffing levels of licensed and non-licensed NPP shift personnel. Minimum staffing levels for the purpose of this study, are defined as those necessary for successful accomplishment of all safety and additional functions that must be performed in order for the licensee to meet applicable regulatory requirements. This project involves a multi-faceted approach to the investigation of the issue. Relevant NRC documentation was identified and reviewed. Using the information obtained from this documentation review, a test plan was developed to aid in the collection of further information regarding the adequacy of current shift staffing levels. The test plan addresses three different activities to be conducted to provide information to the NRC for use in the assessment of current minimum staffing levels. The first activity is collection of data related to industry shift staffing practices through site visits to seven nuclear power plants. The second activity is a simulator study, which will use licensed operator crews responding to a simulated event, under two different staffing levels. Finally, workload models will be constructed for both licensed and non-licensed personnel, using a priori knowledge of the simulator scenarios with data resulting from one of the staffing levels studied in the simulator, and the data collected from the site visits. The model will then be validated against the data obtained from the second staffing level studied in the simulator. The validated model can then be used to study the impact of changing staffing-related variables on the plant shift crew`s ability to effectively mitigate an event.

  20. Temperature and level measurements realized for Nuclear Safety Level Improvement of Slovak NPPs

    International Nuclear Information System (INIS)

    Badiar, S.; Slanina, M.; Stanc, S.; Golan, P.; Krupa, J.

    2001-01-01

    Process of continual safety improvement in the individual Slovak nuclear power plants has been in progress since the beginning of nineties with the objective to upgrade the safety level of units in operation up to the European standards. In the framework of these activities, safety instrumentation systems with 1E qualification for the control of WWER reactor coolant systems were built and added. Methods for implementation of safety instrumentation systems for monitoring temperature and level in reactor coolant systems in the particular plants in Slovakia are presented showing the objectives and methods of their implementation. (Authors)

  1. Innovative designs for low-level nuclear waste disposal trenches

    International Nuclear Information System (INIS)

    Nowatzki, E.A.; Armstrong, G.; McCray, J.

    1985-01-01

    Shallow land burial of low-level nuclear wastes presents many problems that are within the scope of civil engineering analysis and design. These include groundwater seepage, surface water runoff and collection, and the subsidence of trench backfills. Unfortunately, at the time the first disposal sites were being developed, major emphasis was placed on the health-physics aspects of the problem with the result that many of the civil engineering aspects were overlooked and severe problems relating to site integrity exist today. This paper presents the results of a U.S. Nuclear Regulatory Commission (USNRC) sponsored research project conducted at the University of Arizona, Tucson, Arizona, to assess trench cap design from the viewpoint of stability, water infiltration, and economy. Full-scale trenches were constructed that incorporated four different designs. These designs range from a relatively simple cap consisting of engineered backfill with a sloping, compacted soil crown to a more complex cap-crown system that incorporates compacted backfill and a steel reinforced soil-cement cap with an overlaying ''wick'' drain. The results of structural and hydrological monitoring over a period of approximately 15 months are presented. Recommendations are made regarding standard design criteria for future sites based on the results of this research

  2. Geology of high-level nuclear waste disposal: an introduction

    International Nuclear Information System (INIS)

    Roxbugh, I.S.

    1987-01-01

    Hazardous waste is produced by the nuclear fuel cycle from mining and milling of uranium ore, refinement and enrichment, reactor use, and during reprocessing of spent fuel. Waste can be classified according to origin, physical state, and levels of radioactivity and radiotoxicity. The method of the long-term waste disposal is based on the degree of the hazard and the length of time (1000 years to millions of years) for the waste to become safe. The International Atomic Energy Agency (IAEA) has classified radioactive waste into five categories (I-V) based on the amount of radioactivity and heat output of the waste. The text is concerned mainly with the two most hazardous categories (I and II). Disposal at various geological sites using proven mining, engineering, and deep drilling techniques has been proposed and studied. An ideal geological repository would have (1) minimum ground water movement, (2) geochemical and mineralogical properties to retard or immobilize the effects of the nuclear waste from reaching the biosphere, (3) thermochemical properties to allow for heat loading without damage, and (4) structural strength for the operational period. Types of geological environments (both undersea and on land) include evaporites, crystalline rocks, and argillaceous deposits. European and North American case histories are described, and there is a glossary and an extensive list of references in this concise review

  3. Nuclear level density and gamma strength function in 64Fe

    Science.gov (United States)

    Smith, M. K.; Spyrou, A.; Ahn, T.; Dombos, A. C.; Liddick, S. N.; Montes, F.; Naqvi, F.; Richman, D.; Schatz, H.; Brown, J.; Childers, K.; Crider, B. P.; Prokop, C. J.; Deleeuw, E.; Deyoung, P. A.; Langer, C.; Lewis, R.; Meisel, Z.; Pereira, J.; Quinn, S. J.; Schmidt, K.; Larsen, A. C.; Guttormsen, M.

    2017-09-01

    The Fe-Cd mass region exhibits enhanced collectivity and an unexpected increased in gamma-decay probability at low energies. These effects could be significant for r-process nucleosynthesis, where masses, beta-decay probabilities, and neutron capture cross sections are among the most important inputs. Neutron capture is notoriously difficult to measure; so the recent development of an indirect technique to constrain neutron-captures far from stability is especially valuable. This is the beta-Oslo method, which allows the extraction of the nuclear level density and gamma-ray strength function to compute neutron-capture cross sections. This work reports on 64Fe, populated via beta-decay of 64Mn at the National Superconducting Cyclotron Laboratory and measured with the 4pi Summing NaI (SuN) total gamma-ray spectrometer.

  4. Geology of high-level nuclear waste disposal

    International Nuclear Information System (INIS)

    Roxburgh, I.S.

    1988-01-01

    The concept of geological disposal is set out by describing the major rock types in terms of their ability to isolate high-level nuclear waste. The advantages and problems posed by particular rock formations are explored and the design and construction of geological repositories is considered, along with the methods used to estimate their safety. It gives special consideration to the use of sea-covered rock and sediment as well as the on-land situation. Throughout the book the various principles and problems inherent in geological disposal are explained and illustrated by reference to a multitude of European and North American case studies, backed up by a large number of tables, figures and an extensive bibliography

  5. Derived intervention levels in early stage of nuclear accident development

    Energy Technology Data Exchange (ETDEWEB)

    Vladar, M; Fojtik, M [Inst. of Preventive and Clinical Medicine, Bratislava (Slovakia); Stubna, M [Research Inst. of Nuclear Power Plants, Bohunuce (Slovakia)

    1996-12-31

    In this paper the measures for protection of health and property of public in the case of nuclear accident are discussed. They are based on optimal application of so called intervention levels. The actual flow of decision depends on: (1) prognosis of mathematical modelling of possible course of nuclear accident, and (2) results of monitoring of radiation situation.The aim of this contribution was to analyze their mutual cooperation and to suggest such procedure of monitoring or radiation situation which could be used for suggestion of protective measures. In this contribution the zones of protection planning in the accident place surrounding for the urgent measures were specified : (1) regulation of free movement of persons; (2) sheltering; (3) iodine prophylaxis; (4) temporary evacuation; (5) long term or permanent emigration. At the specification of zones of planned protection it is also coming out that regulation of movement of persons, sheltering and iodine prophylaxis were ordered in advance based on the evaluation of the crashed establishment state. In such situation the decision on protective measures in the time interval 6 to 12 hours after the beginning of accidental release is forwarding to: withdrawing the accepted orders on measures and transition from sheltering to temporary evacuation. The criterion for temporary evacuation is: (1) probability of exceeding the effective dose 100 mSv for children up to 10 years of age and pregnant women and 500 mSv for other population within 48 hours after beginning of accidental release; (2) probability of averting the effective dose 50 mSv up to 7 days, 100 mSv up to 15 days and 150 mSv up to 30 days for all population groups. In next part the intervention level, interpretation of values of kerma dose rate in air and determination of the size of planned protection zones are discussed. (J.K.) 3 tabs.

  6. Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level.

    Science.gov (United States)

    Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

    2016-05-01

    An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Numerical schemes for explosion hazards

    International Nuclear Information System (INIS)

    Therme, Nicolas

    2015-01-01

    In nuclear facilities, internal or external explosions can cause confinement breaches and radioactive materials release in the environment. Hence, modeling such phenomena is crucial for safety matters. Blast waves resulting from explosions are modeled by the system of Euler equations for compressible flows, whereas Navier-Stokes equations with reactive source terms and level set techniques are used to simulate the propagation of flame front during the deflagration phase. The purpose of this thesis is to contribute to the creation of efficient numerical schemes to solve these complex models. The work presented here focuses on two major aspects: first, the development of consistent schemes for the Euler equations, then the buildup of reliable schemes for the front propagation. In both cases, explicit in time schemes are used, but we also introduce a pressure correction scheme for the Euler equations. Staggered discretization is used in space. It is based on the internal energy formulation of the Euler system, which insures its positivity and avoids tedious discretization of the total energy over staggered grids. A discrete kinetic energy balance is derived from the scheme and a source term is added in the discrete internal energy balance equation to preserve the exact total energy balance at the limit. High order methods of MUSCL type are used in the discrete convective operators, based solely on material velocity. They lead to positivity of density and internal energy under CFL conditions. This ensures that the total energy cannot grow and we can furthermore derive a discrete entropy inequality. Under stability assumptions of the discrete L8 and BV norms of the scheme's solutions one can prove that a sequence of converging discrete solutions necessarily converges towards the weak solution of the Euler system. Besides it satisfies a weak entropy inequality at the limit. Concerning the front propagation, we transform the flame front evolution equation (the so called

  8. IAEA advisory group meeting on basic and applied problems of nuclear level densities

    International Nuclear Information System (INIS)

    Bhat, M.R.

    1983-06-01

    Separate entries were made in the data base for 17 of the 19 papers included. Two papers were previously included in the data base. Workshop reports are included on (1) nuclear level density theories and nuclear model reaction cross-section calculations and (2) extraction of nuclear level density information from experimental data

  9. Harmonization of nuclear and radiation safety regulations for nuclear power plants with reference levels of Western European Nuclear Regulators Association (WENRA)

    International Nuclear Information System (INIS)

    Bojchuk, V.S.; Mikolajchuk, O.A.; Gromov, G.V.; Dibach, O.M.; Godovanyuk, G.M.; Nosovs'kij, A.V.

    2014-01-01

    Self-evaluation of the Ukrainian regulations on nuclear and radiation safety that apply to nuclear power plants for compliance with the reference levels of the Western European Nuclear Regulators Association (WENRA) is presented. Proposals on improvement of the regulations upon self-evaluation are provided

  10. Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level

    International Nuclear Information System (INIS)

    Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

    2016-01-01

    An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period. - Highlights: • An advanced Gaussian-type trajectory model to evaluate the evacuation zone at Nuclear Power Plant 4 in Taiwan. • Mean land area of Taiwan in becoming the permanent evacuation zone is 11%. • The probabilities of the northern

  11. Symposium on the development of nuclear waste policy: Siting the high-level nuclear waste repository

    International Nuclear Information System (INIS)

    Pijawka, K.D.; Mushkatel, A.H.

    1991-01-01

    The Nuclear Waste Policy Act of 1982 (NWPA) attempted to formulate a viable national policy for managing the disposal of high-level nuclear wastes. The NWPA authorized the selection of two repository sites: the first to be constructed in the West and a second site developed in the eastern United States. A detailed process for site selection was outlined in the NWPA. In addition, the NWPA authorized open-quotes the development of a waste transportation system; required the Department of Energy (DOE) to submit a proposal to construct a facility for monitored retrievable storage (MRS) after conducting a study of the need for, and feasibility of such a facility; and required the President to evaluate the use of the repositories ... for the disposal of high-level waste resulting from defense activitiesclose quotes (DOE, 1988, p. 1). A series of provisions granting oversight participation to states and Indian tribes, as well as a compensation package for the ultimate host state were also included. Responsibility for implementing the NWPA was assigned to DOE

  12. The precautionary principle and high-level nuclear waste policy

    International Nuclear Information System (INIS)

    Frishman, S.

    1999-01-01

    The 'Precautionary Principle' has grown from the broadening observation that there is compelling evidence that damage to humans and the world-wide environment is of such a magnitude and seriousness that new principles for conducting human activities are necessary. One of the various statements of the Precautionary Principle is: when an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. The use of a precautionary principle was a significant recommendation emerging from the 1992 United Nations Conference on Environment and Development, held in Rio de Janeiro, Brazil, and it is gaining acceptance in discussions ranging from global warming to activities that affect the marine environment, and far beyond. In the US high-level nuclear waste policy, there is a growing trend on the part of geologic repository proponents and regulators to shift the required safety evaluation from a deterministic analysis of natural and engineered barriers and their interactions to risk assessments and total system waste containment and isolation performance assessment. This is largely a result of the realisation that scientific 'proof' of safety cannot be demonstrated to the level repository proponents have led the American public to expect. Therefore, they are now developing other methods in an attempt to effectively lower the repository safety expectations of the public. Implicit in this shift in demonstration of 'proof' is that levels of uncertainty far larger than those generally taken as scientifically acceptable must be accepted in repository safety, simply because greater certainty is either too costly, in time and money, or impossible to achieve at the potential Yucca Mountain repository site. In the context of the Precautionary Principle, the repository proponent must bear the burden of providing 'Acceptable' proof, established by an open

  13. Repository schemes for high-level radioactive waste disposal. Report on task no. 1(b)- Review of schemes for argillaceous and saliferous formations

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    This Report examines international proposals for the underground storage of high level radioactive waste. From this study proposals have been developed in relation to conditions that can be expected in the United Kingdom. This Report is restricted to the consideration of repositories in the softer rocks, the clays and the shales which can be encountered in many parts of the United Kingdom. It has also considered the construction of a repository in rock salt. The only such deposits which could be developed for the purpose are found under the North Sea. For the purpose of this Study it has been assumed that suitable sites can be located near enough to a coast line to allow works to be constructed from the land. The likely cost of a repository will vary widely depending upon the nature of the ground in which it is constructed and the depth. The choice here is not an engineering matter but is dictated by the degree of protection which it is necessary to give to the environment, both within the forseeable future and for many generations to come. Costs are estimated making various assumptions.

  14. Synroc - a multiphase ceramic for high level nuclear waste immobilisation

    International Nuclear Information System (INIS)

    Reeve, K.D.; Vance, E.R.; Hart, K.P.; Smith, K.L.; Lumpkin, G.R.; Mercer, D.J.

    1992-01-01

    Many natural minerals - particularly titanates - are very durable geochemically, having survived for millions of years with very little alteration. Moreover, some of these minerals have quantitatively retained radioactive elements and their daughter products over this time. The Synroc concept mimics nature by providing an all-titanate synthetic mineral phase assemblage to immobilise high level waste (HLW) from nuclear fuel reprocessing operations for safe geological disposal. In principle, many chemically hazardous inorganic wastes arising from industry could also be immobilised in highly durable ceramics and disposed of geologically, but in practice the cost structure of most industries is such that lower cost waste management solutions - for example, the development of reusable by-products or the use of cements rather than ceramics - have to be devised. In many thousands of aqueous leach tests at ANSTO, mostly at 70-90 deg C, Synroc has been shown to be exceptionally durable. The emphases of the recent ANSTO program have been on tailoring of the Synroc composition to varying HLW compositions, leach testing of Synroc containing radioactive transuranic actinides, study of leaching mechanisms by SEM and TEM, and the development and costing of a conceptual fully active Synroc fabrication plant design. A summary of recent results on these topics will be presented. 29 refs., 4 figs

  15. Reinforced concrete in the intermediable-level nuclear waste repository

    International Nuclear Information System (INIS)

    Duffo, Gustavo

    2009-01-01

    The National Atomic Energy Commission (CNEA) is responsible for developing the nuclear waste disposal management programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is a near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers and the model foresees a period of 300 years of institutional post-closure control. Since the vault and cover are major components of the engineered barriers, the durability of these concrete structures is an important aspect for the facility integrity. This work presents laboratory investigations performed on the corrosion susceptibility of steel rebars embedded in two different types of high performance reinforced concretes, recently developed by the National Institute of Industrial Technology (Argentine). Concretes were made with cement with Blast Furnace Slag (CAH) and Silica Fume cement (CAH + SF). The aim of this work is to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. Besides, the diffusion coefficients of aggressive species, such as chloride and carbon dioxide, were also determined. On the other hand, data obtained with corrosion sensors embedded in a vault prototype is also included. These sensors allow on-line measurements of several parameters related to the corrosion process such as rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity; chloride concentration and internal concrete temperature. All the information obtained from both, laboratory tests and sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of

  16. Intracellular calcium levels can regulate Importin-dependent nuclear import

    International Nuclear Information System (INIS)

    Kaur, Gurpreet; Ly-Huynh, Jennifer D.; Jans, David A.

    2014-01-01

    Highlights: • High intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import. • The effect of Ca 2+ on nuclear import does not relate to changes in the nuclear pore. • High intracellular calcium can result in mislocalisation of Impβ1, Ran and RCC1. - Abstract: We previously showed that increased intracellular calcium can modulate Importin (Imp)β1-dependent nuclear import of SRY-related chromatin remodeling proteins. Here we extend this work to show for the first time that high intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import generally. The basis of this relates to the mislocalisation of the transport factors Impβ1 and Ran, which show significantly higher nuclear localization in contrast to various other factors, and RCC1, which shows altered subnuclear localisation. The results here establish for the first time that intracellular calcium modulates conventional nuclear import through direct effects on the nuclear transport machinery

  17. Intracellular calcium levels can regulate Importin-dependent nuclear import

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Gurpreet; Ly-Huynh, Jennifer D.; Jans, David A., E-mail: David.Jans@monash.edu

    2014-07-18

    Highlights: • High intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import. • The effect of Ca{sup 2+} on nuclear import does not relate to changes in the nuclear pore. • High intracellular calcium can result in mislocalisation of Impβ1, Ran and RCC1. - Abstract: We previously showed that increased intracellular calcium can modulate Importin (Imp)β1-dependent nuclear import of SRY-related chromatin remodeling proteins. Here we extend this work to show for the first time that high intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import generally. The basis of this relates to the mislocalisation of the transport factors Impβ1 and Ran, which show significantly higher nuclear localization in contrast to various other factors, and RCC1, which shows altered subnuclear localisation. The results here establish for the first time that intracellular calcium modulates conventional nuclear import through direct effects on the nuclear transport machinery.

  18. Transient three-dimensional thermal-hydraulic analysis of nuclear reactor fuel rod arrays: general equations and numerical scheme

    International Nuclear Information System (INIS)

    Wnek, W.J.; Ramshaw, J.D.; Trapp, J.A.; Hughes, E.D.; Solbrig, C.W.

    1975-11-01

    A mathematical model and a numerical solution scheme for thermal-hydraulic analysis of fuel rod arrays are given. The model alleviates the two major deficiencies associated with existing rod array analysis models, that of a correct transverse momentum equation and the capability of handling reversing and circulatory flows. Possible applications of the model include steady state and transient subchannel calculations as well as analysis of flows in heat exchangers, other engineering equipment, and porous media

  19. Numerical design of RNnν symmetry-based RF pulse schemes for recoupling and decoupling of nuclear spin interactions at high MAS frequencies

    International Nuclear Information System (INIS)

    Herbst, Christian; Herbst, Jirada; Leppert, Joerg; Ohlenschlaeger, Oliver; Goerlach, Matthias; Ramachandran, Ramadurai

    2009-01-01

    An approach for the efficient implementation of RN n ν symmetry-based pulse schemes that are often employed for recoupling and decoupling of nuclear spin interactions in biological solid state NMR investigations is demonstrated at high magic-angle spinning frequencies. RF pulse sequences belonging to the RN n ν symmetry involve the repeated application of the pulse sandwich {R φ R -φ }, corresponding to a propagator U RF = exp(-i4φI z ), where φ = πν/N and R is typically a pulse that rotates the nuclear spins through 180 o about the x-axis. In this study, broadband, phase-modulated 180 o pulses of constant amplitude were employed as the initial 'R' element and the phase-modulation profile of this 'R' element was numerically optimised for generating RN n ν symmetry-based pulse schemes with satisfactory magnetisation transfer characteristics. At representative MAS frequencies, RF pulse sequences were implemented for achieving 13 C- 13 C double-quantum dipolar recoupling and through bond scalar coupling mediated chemical shift correlation and evaluated via numerical simulations and experimental measurements. The results from these investigations are presented here

  20. Riemann-problem and level-set approaches for two-fluid flow computations I. Linearized Godunov scheme

    NARCIS (Netherlands)

    B. Koren (Barry); M.R. Lewis; E.H. van Brummelen (Harald); B. van Leer

    2001-01-01

    textabstractA finite-volume method is presented for the computation of compressible flows of two immiscible fluids at very different densities. The novel ingredient in the method is a two-fluid linearized Godunov scheme, allowing for flux computations in case of different fluids (e.g., water and

  1. Computer-based control of nuclear power information systems at international level

    International Nuclear Information System (INIS)

    Boniface, Ekechukwu; Okonkwo, Obi

    2011-01-01

    In most highly industrialized countries of the world information plays major role in anti-nuclear campaign. Information and discussions on nuclear power need critical and objective analysis before the structured information presentation to the public to avoid bias anti-nuclear information on one side and neglect of great risk in nuclear power. This research is developing a computer-based information system for the control of nuclear power at international level. The system is to provide easy and fast information highways for the followings: (1) Low Regulatory dose and activity limit as level of high danger for individuals and public. (2) Provision of relevant technical or scientific education among the information carriers in the nuclear power countries. The research is on fact oriented investigation about radioactivity. It also deals with fact oriented education about nuclear accidents and safety. A standard procedure for dissemination of latest findings using technical and scientific experts in nuclear technology is developed. The information highway clearly analyzes the factual information about radiation risk and nuclear energy. Radiation cannot be removed from our environment. The necessity of radiation utilizations defines nuclear energy as two-edge sword. It is therefore, possible to use computer-based information system in projecting and dissemination of expert knowledge about nuclear technology positively and also to use it in directing the public on the safety and control of the nuclear energy. The computer-based information highway for nuclear energy technology is to assist in scientific research and technological development at international level. (author)

  2. Threat of nuclear violence at the non-governmental level

    International Nuclear Information System (INIS)

    Feld, B.T.

    1982-01-01

    Safeguarding nuclear weapons from falling into the hands of non-governmental terrorist groups is discussed. Political and technical solutions are seen as necessary before international action can be achieved

  3. Radiological safety for the public during nuclear emergencies: application of intervention levels and derived intervention levels

    International Nuclear Information System (INIS)

    Thomas, G.; Kumar, K.S.

    2006-01-01

    Control of radiation exposures to the public following a major nuclear accident can be achieved through intervention by implementing countermeasures such as sheltering, iodine prophylaxis, evacuation, control of foodstuff, etc. Intervention levels (I.L.) are formulated such that exposure to individuals from all exposure pathways is well below the thresholds for deterministic effects, and risk of stochastic health effects to individuals and overall incidence of stochastic effects in the exposed population are minimized. It is also necessary to translate such I.L. into quantities, called derived intervention levels (D.I.L.) that can be measured. The I.L. followed in various countries for the recommended countermeasures cater to the exposure range of 1-50 mSv for sheltering, 10-500 mSv for evacuation, 30- 1000 mSv for iodine prophylaxis and 1-10 mSv for food control. The models used for these are based on conservative estimations assuming maximum dose delivered to the critical group for the pathway assumed. While the concept of upper dose level above which countermeasures is always justified to avoid deterministic effects, the lower range of dose levels have to be optimised based on various parameters as discussed in this paper. While arriving at the I.L., the question to be addressed is: How much (dose) risk should be averted by the intervention planned? Implementation of any countermeasure will result in some inconvenience/ limitation of resource/ disruption and consequently, a positive net benefit will justify the intervention. Sheltering may result in substantially less disruption than evacuation, but if the type of sheltering is not offering enough radiation shielding or ventilation protection, this may not result in significant reduction of exposure. It is to be ensured that deterministic effects are totally avoided and it is possible to define a safe threshold exposure and above which balancing risks and benefits is not applicable. While the dose limit for the

  4. Spent nuclear fuel project high-level information management plan

    Energy Technology Data Exchange (ETDEWEB)

    Main, G.C.

    1996-09-13

    This document presents the results of the Spent Nuclear Fuel Project (SNFP) Information Management Planning Project (IMPP), a short-term project that identified information management (IM) issues and opportunities within the SNFP and outlined a high-level plan to address them. This high-level plan for the SNMFP IM focuses on specific examples from within the SNFP. The plan`s recommendations can be characterized in several ways. Some recommendations address specific challenges that the SNFP faces. Others form the basis for making smooth transitions in several important IM areas. Still others identify areas where further study and planning are indicated. The team`s knowledge of developments in the IM industry and at the Hanford Site were crucial in deciding where to recommend that the SNFP act and where they should wait for Site plans to be made. Because of the fast pace of the SNFP and demands on SNFP staff, input and interaction were primarily between the IMPP team and members of the SNFP Information Management Steering Committee (IMSC). Key input to the IMPP came from a workshop where IMSC members and their delegates developed a set of draft IM principles. These principles, described in Section 2, became the foundation for the recommendations found in the transition plan outlined in Section 5. Availability of SNFP staff was limited, so project documents were used as a basis for much of the work. The team, realizing that the status of the project and the environment are continually changing, tried to keep abreast of major developments since those documents were generated. To the extent possible, the information contained in this document is current as of the end of fiscal year (FY) 1995. Programs and organizations on the Hanford Site as a whole are trying to maximize their return on IM investments. They are coordinating IM activities and trying to leverage existing capabilities. However, the SNFP cannot just rely on Sitewide activities to meet its IM requirements

  5. Nuclear size is sensitive to NTF2 protein levels in a manner dependent on Ran binding

    Science.gov (United States)

    Vuković, Lidija D.; Jevtić, Predrag; Zhang, Zhaojie; Stohr, Bradley A.; Levy, Daniel L.

    2016-01-01

    ABSTRACT Altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. Although nuclear import rates generally positively correlate with nuclear size, NTF2 levels negatively affect nuclear size, despite the role of NTF2 (also known as NUTF2) in nuclear recycling of the import factor Ran. We show that binding of Ran to NTF2 is required for NTF2 to inhibit nuclear expansion and import of large cargo molecules in Xenopus laevis egg and embryo extracts, consistent with our observation that NTF2 reduces the diameter of the nuclear pore complex (NPC) in a Ran-binding-dependent manner. Furthermore, we demonstrate that ectopic NTF2 expression in Xenopus embryos and mammalian tissue culture cells alters nuclear size. Finally, we show that increases in nuclear size during melanoma progression correlate with reduced NTF2 expression, and increasing NTF2 levels in melanoma cells is sufficient to reduce nuclear size. These results show a conserved capacity for NTF2 to impact on nuclear size, and we propose that NTF2 might be a new cancer biomarker. PMID:26823604

  6. Experimental study of nuclear models. I. Decay schemes and nuclear reactions. II. Muonic x-ray studies. Progress report, October 1, 1974--September 30, 1975

    International Nuclear Information System (INIS)

    Sheline, R.K.

    1975-01-01

    Progress on the research on our AT-(40-1)-2434 Contract is summarized for the twelve month contract year beginning October 1, 1974, and ending September 30, 1975. The main emphasis of our research continues to be an experimental study of nuclear models. Some change of emphasis is occurring. In the past, the emphasis has been overwhelmingly nuclear reaction spectroscopy and comparison with theoretical models. This year an increasing percentage of the emphasis (perhaps 25 percent) is on the study of nuclear structure from the view point of muonic x-ray spectroscopy. A list of publications is included. (U.S.)

  7. Calculation of nuclear level density parameters of some light deformed medical radionuclides using collective excitation modes of observed nuclear spectra

    International Nuclear Information System (INIS)

    Okuducu, S.; Sarac, H.; Akti, N. N.; Boeluekdemir, M. H.; Tel, E.

    2010-01-01

    In this study the nuclear energy level density based on nuclear collective excitation mechanism has been identified in terms of the low-lying collective level bands at near the neutron binding energy. Nuclear level density parameters of some light deformed medical radionuclides used widely in medical applications have been calculated by using different collective excitation modes of observed nuclear spectra. The calculated parameters have been used successfully in estimation of the neutron-capture cross section basic data for the production of new medical radionuclides. The investigated radionuclides have been considered in the region of mass number 40< A< 100. The method used in the present work assumes equidistance spacing of the collective coupled state bands of the interest radionuclides. The present calculated results have been compared with the compiled values from the literatures for s-wave neutron resonance data.

  8. Actinide Isotope Ratios Measured by Resonance Ionization Mass Spectrometry: Optimization of Ionization Schemes and Demonstration Using Nuclear Fallout

    Science.gov (United States)

    2017-12-01

    9 2. The Time -Dependent Schrödinger Equation ............................12 3. Stimulated Excitation to Bound States...response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and...SNM Special Nuclear Material TDC Time to Digital Converter Ti:Saph Titanium Sapphire TOF-MS Time -of-Flight Mass Spectrometry xvi THIS

  9. A Velocity-Level Bi-Criteria Optimization Scheme for Coordinated Path Tracking of Dual Robot Manipulators Using Recurrent Neural Network.

    Science.gov (United States)

    Xiao, Lin; Zhang, Yongsheng; Liao, Bolin; Zhang, Zhijun; Ding, Lei; Jin, Long

    2017-01-01

    A dual-robot system is a robotic device composed of two robot arms. To eliminate the joint-angle drift and prevent the occurrence of high joint velocity, a velocity-level bi-criteria optimization scheme, which includes two criteria (i.e., the minimum velocity norm and the repetitive motion), is proposed and investigated for coordinated path tracking of dual robot manipulators. Specifically, to realize the coordinated path tracking of dual robot manipulators, two subschemes are first presented for the left and right robot manipulators. After that, such two subschemes are reformulated as two general quadratic programs (QPs), which can be formulated as one unified QP. A recurrent neural network (RNN) is thus presented to solve effectively the unified QP problem. At last, computer simulation results based on a dual three-link planar manipulator further validate the feasibility and the efficacy of the velocity-level optimization scheme for coordinated path tracking using the recurrent neural network.

  10. Draft emergency action level guidelines for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-09-15

    This document is provided for interim use during the initial phases of the NRC effort to promptly improve emergency preparedness at operating nuclear power plants. Changes to the document can be expected as experience is gained in its use and public comments are received. Further, the Commission has initiated a rulemaking procedure, now scheduled for completion in January 1930 in the area of Emergency Planning and Preparedness. Additional requirements are to be expected when rulemaking is completed and some modifications to this document may be necessary. Four classes of Emergency Action Levels are established which replace the classes in Regulatory Guide 1.101, each with associated examples of initiating conditions. The classes are: - Notification of Unusual Event; - Alert; - Site Emergency; - General Emergency. The rationale for the notification and alert classes is to provide early and prompt notification of minor events which could lead to more serious consequences given operator error or equipment failure or which might be indicative of more serious conditions which are not yet fully realized. A gradation is provided to assure fuller response preparations for more serious indicators. The site emergency class reflects conditions where some significant releases are likely or are occurring but where a core melt situation is not indicated based on current information. In this situation full mobilization of emergency personnel in tie :near site environs is indicated as well as dispatch of monitoring teams and associated communications. The general emergency class involves actual or imminent substantial core degradation or malting with the potential for loss of containment. The immediate action for this class is sheltering (staying inside) rather thai evacuation until an assessment can be made that (1) an evacuation is indicated and (2) an evacuation, if indicated, can be completed prior to significant release and transport of radioactive material to the affected

  11. Draft emergency action level guidelines for nuclear power plants

    International Nuclear Information System (INIS)

    1979-09-01

    This document is provided for interim use during the initial phases of the NRC effort to promptly improve emergency preparedness at operating nuclear power plants. Changes to the document can be expected as experience is gained in its use and public comments are received. Further, the Commission has initiated a rulemaking procedure, now scheduled for completion in January 1930 in the area of Emergency Planning and Preparedness. Additional requirements are to be expected when rulemaking is completed and some modifications to this document may be necessary. Four classes of Emergency Action Levels are established which replace the classes in Regulatory Guide 1.101, each with associated examples of initiating conditions. The classes are: - Notification of Unusual Event; - Alert; - Site Emergency; - General Emergency. The rationale for the notification and alert classes is to provide early and prompt notification of minor events which could lead to more serious consequences given operator error or equipment failure or which might be indicative of more serious conditions which are not yet fully realized. A gradation is provided to assure fuller response preparations for more serious indicators. The site emergency class reflects conditions where some significant releases are likely or are occurring but where a core melt situation is not indicated based on current information. In this situation full mobilization of emergency personnel in tie :near site environs is indicated as well as dispatch of monitoring teams and associated communications. The general emergency class involves actual or imminent substantial core degradation or malting with the potential for loss of containment. The immediate action for this class is sheltering (staying inside) rather thai evacuation until an assessment can be made that (1) an evacuation is indicated and (2) an evacuation, if indicated, can be completed prior to significant release and transport of radioactive material to the affected

  12. Preparedness and planning for nuclear accidents at national level

    International Nuclear Information System (INIS)

    Shiukshta, A.

    1998-01-01

    National plan for the protection of population in the case in nuclear accident at Ignalina NPP is presented. The plan was elaborated and approved in 1995, tested in a number of training and practical operations and positively evaluated by experts. The plan provides for measures of protection, their scope, schedule, executive officers and organizations and procedure of implementation

  13. Fingerprints of single nuclear spin energy levels using STM - ENDOR.

    Science.gov (United States)

    Manassen, Yishay; Averbukh, Michael; Jbara, Moamen; Siebenhofer, Bernhard; Shnirman, Alexander; Horovitz, Baruch

    2018-04-01

    We performed STM-ENDOR experiments where the intensity of one of the hyperfine components detected in ESR-STM is recorded while an rf power is irradiated into the tunneling junction and its frequency is swept. When the latter frequency is near a nuclear transition a dip in ESR-STM signal is observed. This experiment was performed in three different systems: near surface SiC vacancies where the electron spin is coupled to a next nearest neighbor 29 Si nucleus; Cu deposited on Si(111)7x7 surface, where the unpaired electron of the Cu atom is coupled to the Cu nucleus ( 63 Cu, 65 Cu) and on Tempo molecules adsorbed on Au(111), where the unpaired electron is coupled to a Nitrogen nucleus ( 14 N). While some of the hyperfine values are unresolved in the ESR-STM data due to linewidth we find that they are accurately determined in the STM-ENDOR data including those from remote nuclei, which are not detected in the ESR-STM spectrum. Furthermore, STM-ENDOR can measure single nuclear Zeeman frequencies, distinguish between isotopes through their different nuclear magnetic moments and detect quadrupole spectra. We also develop and solve a Bloch type equation for the coupled electron-nuclear system that facilitates interpretation of the data. The improved spectral resolution of STM - ENDOR opens many possibilities for nanometric scale chemical analysis. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. A Study of KHNP Nuclear Power Plant Technology Level Evaluation

    International Nuclear Information System (INIS)

    Yang, Seung Han; Lee, Sung Jin; Kim, Yo Han

    2016-01-01

    KHNP's 2030 mid and long term plan goal in technology field is securing global No. 1 NPP technology level. Quantifying technology level for this purpose, technology level at present should be surveyed. Technology level of South Korea has been surveyed by KISTEP (Korea Institute of S and T Evaluation and Planning) every two year but the technology level of KHNP has not been surveyed by any organization including KHNP itself. Also the size of technology surveyed by KISTEP was too broad to quantifying technology level of KHNP. In this paper, technology level of KHNP and South Korea are presented. In this study, NPP related technologies were divided into Level I and Level II technologies and conducted a survey for each Level II technologies using Delphi questionnaire survey that is widely used in technology level evaluation. The results of technology level and gap will be used from strategic point of view and also as a reference data for technology improvement planning

  15. A Study of KHNP Nuclear Power Plant Technology Level Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seung Han; Lee, Sung Jin; Kim, Yo Han [KHNP, Daejeon (Korea, Republic of)

    2016-05-15

    KHNP's 2030 mid and long term plan goal in technology field is securing global No. 1 NPP technology level. Quantifying technology level for this purpose, technology level at present should be surveyed. Technology level of South Korea has been surveyed by KISTEP (Korea Institute of S and T Evaluation and Planning) every two year but the technology level of KHNP has not been surveyed by any organization including KHNP itself. Also the size of technology surveyed by KISTEP was too broad to quantifying technology level of KHNP. In this paper, technology level of KHNP and South Korea are presented. In this study, NPP related technologies were divided into Level I and Level II technologies and conducted a survey for each Level II technologies using Delphi questionnaire survey that is widely used in technology level evaluation. The results of technology level and gap will be used from strategic point of view and also as a reference data for technology improvement planning.

  16. An extrapolation scheme for solid-state NMR chemical shift calculations

    Science.gov (United States)

    Nakajima, Takahito

    2017-06-01

    Conventional quantum chemical and solid-state physical approaches include several problems to accurately calculate solid-state nuclear magnetic resonance (NMR) properties. We propose a reliable computational scheme for solid-state NMR chemical shifts using an extrapolation scheme that retains the advantages of these approaches but reduces their disadvantages. Our scheme can satisfactorily yield solid-state NMR magnetic shielding constants. The estimated values have only a small dependence on the low-level density functional theory calculation with the extrapolation scheme. Thus, our approach is efficient because the rough calculation can be performed in the extrapolation scheme.

  17. Scheme of higher-density storage of spent nuclear fuel in Chernobyl NPP interim storage facility no. 1

    International Nuclear Information System (INIS)

    Britan, P.M.

    2008-01-01

    On 29. March 2000 the Cabinet of Ministers of Ukraine issued a decree prescribing that the last operating unit of Chernobyl NPP be shut down before its design lifetime expiry. In accordance with the Contract concluded on 14 June 1999 between the National Energy-generating Company 'Energoatom' and the Consortium of Framatome, Campenon Bernard-SGE and Bouygues, in order to store the spent ChNPP fuel a new interim dry storage facility (ISF-2) for spent ChNPP fuel would be built. Currently the spent nuclear fuel (spent fuel assemblies - SFAs) is stored in reactor cooling pools and in the reactors on Units 1, 2, 3, as well as in the wet Interim Storage Facility (ISF-1). Taking into account the expected delay with the commissioning of ISF-2, and in connection with the scheduled activities to build the New Safe Confinement (including the taking-down of the existing ventilation stack of ChNPP Units 3 and 4) and the expiry of the design operation life of Units 1 and 2, it is expedient to remove the nuclear fuel from Units 1, 2 and 3. This is essential to improve nuclear safety and ensure that the schedule of construction of the New Safe Confinement is met. The design capacity of ISF-1 (17 800 SFAs) is insufficient to store all SFAs (21 284) currently on ChNPP. A technically feasible option that has been applied on other RBMK plants is denser storage of spent nuclear fuel in the cooling ponds of the existing ISF-1. The purpose of the proposed modifications is to introduce changes to the ISF-1 design supported by necessary justifications required by the Ukrainian codes with the objective of enabling the storage of additional SFAs in the existing storage space (cooling pools). The need for the modification is caused by the requirement to remove nuclear fuel from the ChNPP units as soon as possible, before the work begins to decommission these units, as well as to create safe conditions for the construction of the New Safe Confinement over the existing Shelter Unit. (author)

  18. Score level fusion scheme based on adaptive local Gabor features for face-iris-fingerprint multimodal biometric

    Science.gov (United States)

    He, Fei; Liu, Yuanning; Zhu, Xiaodong; Huang, Chun; Han, Ye; Chen, Ying

    2014-05-01

    A multimodal biometric system has been considered a promising technique to overcome the defects of unimodal biometric systems. We have introduced a fusion scheme to gain a better understanding and fusion method for a face-iris-fingerprint multimodal biometric system. In our case, we use particle swarm optimization to train a set of adaptive Gabor filters in order to achieve the proper Gabor basic functions for each modality. For a closer analysis of texture information, two different local Gabor features for each modality are produced by the corresponding Gabor coefficients. Next, all matching scores of the two Gabor features for each modality are projected to a single-scalar score via a trained, supported, vector regression model for a final decision. A large-scale dataset is formed to validate the proposed scheme using the Facial Recognition Technology database-fafb and CASIA-V3-Interval together with FVC2004-DB2a datasets. The experimental results demonstrate that as well as achieving further powerful local Gabor features of multimodalities and obtaining better recognition performance by their fusion strategy, our architecture also outperforms some state-of-the-art individual methods and other fusion approaches for face-iris-fingerprint multimodal biometric systems.

  19. High system-safety level of nuclear power stations

    International Nuclear Information System (INIS)

    Lutz, H.R.

    1976-01-01

    A bluntly worded disquisition contrasting the incidence of death and harm to persons in the chemical industry with the low hazards in nuclear power stations. Quotes conclusions from a U.S. accident study that the risk from 100 large power stations is 100 times smaller than from chlorine manufacture and transport. The enclosure of a reactor in a safety container, the well understood effects of radioactivity on man, and the ease of measuring leakage well below safe limits, are safety features which he considers were not matched in the products and plant of the Seveso factory which suffered disaster. Questions the usefulness of warnings about nuclear dangers when chemical dangers are much greater and road dangers very much greater still. (R.W.S.)

  20. Reduction and resource recycling of high-level radioactive wastes through nuclear transmutation with PHITS code

    International Nuclear Information System (INIS)

    Fujita, Reiko

    2017-01-01

    In the ImPACT program of the Cabinet Office, programs are underway to reduce long-lived fission products (LLFP) contained in high-level radioactive waste through nuclear transmutation, or to recycle/utilize useful nuclear species. This paper outlines this program and describes recent achievements. This program consists of five projects: (1) separation/recovery technology, (2) acquisition of nuclear transmutation data, (3) nuclear reaction theory model and simulation, (4) novel nuclear reaction control and development of elemental technology, and (5) discussions on process concept. The project (1) develops a technology for dissolving vitrified solid, a technology for recovering LLFP from high-level waste liquid, and a technology for separating odd and even lasers. Project (2) acquires the new nuclear reaction data of Pd-107, Zr-93, Se-79, and Cs-135 using RIKEN's RIBF or JAEA's J-PARC. Project (3) improves new nuclear reaction theory and structural model using the nuclear reaction data measured in (2), improves/upgrades nuclear reaction simulation code PHITS, and proposes a promising nuclear transmutation pathway. Project (4) develops an accelerator that realizes the proposed transmutation route and its elemental technology. Project (5) performs the conceptual design of the process to realize (1) to (4), and constructs the scenario of reducing/utilizing high-level radioactive waste to realize this design. (A.O.)

  1. The behaviour of the lande factor and effective exchange parameter in a group of Pr intermetallics observed through reduced level scheme models

    International Nuclear Information System (INIS)

    Ranke, P.J. von; Caldas, A.; Palermo, L.

    1993-01-01

    The present work constitutes a portion of a continuing series of studies dealing with models, in which we retain only the two lowest levels of the crystal field splitting scheme of rare-earth ion in rare-earth intermetallics. In these reduced level scheme models, the crystal field and the magnetic Hamiltonians are represented in matrix notation. These two matrices constitute the model Hamiltonian proposed in this paper, from which we derive the magnetic state equations of interest for this work. Putting into these equations a group of adequate experimental data found in the literature for a particular rare-earth intermetallic we obtain the Lande factor and effective exchange parameter related to this rare-earth intermetallic. This study will be applied to a group of Pr intermetallics, in cubic symmetry, in which the ground level may be a non-magnetic singlet level or a non-magnetic doublet level. In both cases, the first excited level is a triplet one. (orig.)

  2. Environmental radioactivity levels, Sequoyah Nuclear Plant. Annual report, 1983

    International Nuclear Information System (INIS)

    1984-04-01

    This report describes the environmental radiological monitoring of the Sequoyah Nuclear Plant (SQN) located in Hamilton County, Tennessee, conducted in 1983. Dose estimates were calculated from concentrations of radioactivity found in samples of air, milk, water, and fish. It was concluded there were no significant increases in the exposure to members of the general public attributable to the operation of SQN. 11 figures, 34 tables

  3. Application of system-level FMEA in the nuclear industry

    International Nuclear Information System (INIS)

    Crocker, W.; Parmar, R.; Salvador, M.; Forystek, A.; Xu, C.

    2012-01-01

    Failure Modes and Effects Analysis (FMEA) is an analytical technique used to assess risk that is applied in various industries such as aerospace, automotive and health care. A recent application in the nuclear industry of FMEA methodology to support the design modification process at a major electrical utility in Ontario is examined. This application of FMEA involves assessing proposed design changes by systematically identifying various component failure modes and their effect on the parent system with respect to the related employee, environmental, production and nuclear safety impact. In doing so, any design weaknesses are identified along with potential corrective actions such as adding redundant components. FMEA is being applied early in the design process with the focus on finding the problems before equipment is installed where failures may manifest into serious safety and economic consequences. To illustrate the application of FMEA in the nuclear industry, the results of a recent study will be presented with a walk through of the analysis process along with overall study findings. The study involved application of FMEA to support a design modification to replace the existing Condenser Steam Dump Valve (CSDV) actuator and top works (associated instrumentation, e.g., solenoid valves) on an operating reactor. (author)

  4. Application of system-level FMEA in the nuclear industry

    Energy Technology Data Exchange (ETDEWEB)

    Crocker, W.; Parmar, R.; Salvador, M. [AMEC NSS Ltd., Toronto, Ontario (Canada); Forystek, A.; Xu, C. [Bruce Power, Tiverton, Ontario (Canada)

    2012-07-01

    Failure Modes and Effects Analysis (FMEA) is an analytical technique used to assess risk that is applied in various industries such as aerospace, automotive and health care. A recent application in the nuclear industry of FMEA methodology to support the design modification process at a major electrical utility in Ontario is examined. This application of FMEA involves assessing proposed design changes by systematically identifying various component failure modes and their effect on the parent system with respect to the related employee, environmental, production and nuclear safety impact. In doing so, any design weaknesses are identified along with potential corrective actions such as adding redundant components. FMEA is being applied early in the design process with the focus on finding the problems before equipment is installed where failures may manifest into serious safety and economic consequences. To illustrate the application of FMEA in the nuclear industry, the results of a recent study will be presented with a walk through of the analysis process along with overall study findings. The study involved application of FMEA to support a design modification to replace the existing Condenser Steam Dump Valve (CSDV) actuator and top works (associated instrumentation, e.g., solenoid valves) on an operating reactor. (author)

  5. Study of numerical schemes for two-phase flow in porous media for any meshes: application to storage of nuclear waste

    International Nuclear Information System (INIS)

    Angelini, O.

    2010-01-01

    The two-phase flow in porous media is a complex phenomenon and which relate to many industrial problems. EDF works on the feasibility and the safety of a storage in deep geologic layer of nuclear waste. In this domain the simulation of the two-phase flow in porous media is particularly important in at least three domains: first of all during the phase of ventilation of the galleries of the storage which could de-saturate the rock and so modify its properties, but also during the phase of re-saturation of the materials and finally during the arrival of the water on the metal parts contained in the storage which will then involve phenomena of corrosion and a hydrogen release. In this context, EDF wishes to obtain robust numerical methods without restrictive condition on the mesh. This work is dedicated at first to the development of the finite volume scheme SUSHI (Scheme Using Stabilization and Hybrid Interfaces) in the code of mechanics of EDF, Code Aster in order to simulate the two-phase flow in porous media. This scheme was developed in 2D and in 3D. At the same time a new formulation which allows to simulate in a uniform way the flows in saturated and unsaturated porous media for miscible and immiscible problems is proposed. Various studies simulating difficulties related to the problems of the storage of nuclear waste in deep geological layers were study. We can quote the study of a bi-material which advances the capillary re-balancing of a material by an other one possessing properties and initial very heterogeneous conditions in saturation. We will also quote the study of the injection of hydrogen in an porous media initially saturated in pure water which is proposed by the benchmark 'two-phase Flow' proposed by the GNR MOMAS. This study had for objective to bring to light the good treatment of the appearance of a phase in a saturated porous media and thus the relevance of our new formulation to study with a way unified a problem of saturated flow and a

  6. Nuclear level density of 166Er with static deformation

    International Nuclear Information System (INIS)

    Nasrabadi, M.N.

    2006-01-01

    The level densities of 166 Er is calculated using the microscopic theory of interacting fermions and is compared with experimental. It is concluded that the data can be reproduced with level density formalism for nuclei with static deformation

  7. Achieving world's highest level of nuclear safety learning from overseas nuclear trouble events

    International Nuclear Information System (INIS)

    Okumoto, Masaru

    2014-01-01

    Nuclear Information Research Project of Institute of Nuclear Safety System, Incorporated (INSS) had acquired trouble information of nuclear power plants (NPPs) up to annual several thousand events issued by overseas regulatory agencies for more than 20 years since INSS established and analyzed it in details respectively after the screening. Lessons extracted from the analysis were offered as suggestions to electric utilities having PWRs in Japan. Such activities would surely contribute to maintain and improve nuclear safety with no objection. However, they could not prevent the occurrence of accident of Fukushima Daiichi NPPs. Thus the project had reviewed usefulness of past activities and how improved could be by listening sincerely to outside opinions. This report introduced outlines of recent activities. Competent suggestions to electric utilities might be made with improved reflection of lessons to needed rules, deepened information sharing within the project and raised awareness of the problem. (T. Tanaka)

  8. French nuclear safety authorities: for a harmonization of nuclear safety at the European level

    International Nuclear Information System (INIS)

    Anon.

    2004-01-01

    The European Commission is working on 2 directives concerning nuclear energy: the first one is dedicated to nuclear safety and the second to the management of radioactive wastes and spent fuels. In the context of the widening of the European Union and of the inter-connection of the different electric power grids throughout Europe, the harmonization of the rules in the nuclear safety field is seen by manufacturers as a mean to achieve a fair competition between nuclear equipment supplying companies and by the French nuclear safety authorities (FNSA) as a mean to keep on improving nuclear safety and to be sure that competitiveness does not drive safety standards down. According to FNSA the 2 European directives could give a legal framework to the harmonization and should contain principles that reinforce the responsibility of each state. FNSA considers that the EPR (European pressurized water reactor) may be an efficient tool for the harmonization because of existing industrial cooperation programs between France and Germany and between France and Finland. (A.C.)

  9. Large model-space calculation of the nuclear level density parameter

    International Nuclear Information System (INIS)

    Agrawal, B.K.; Samaddar, S.K.; De, J.N.; Shlomo, S.

    1998-01-01

    Recently, several attempts have been made to obtain nuclear level density (ρ) and level density parameter (α) within the microscopic approaches based on path integral representation of the partition function. The results for the inverse level density parameter K es and the level density as a function of excitation energy are presented

  10. Corrosion issues in high-level nuclear waste containers

    Science.gov (United States)

    Asl, Samin Sharifi

    In this dissertation different aspects of corrosion and electrochemistry of copper, candidate canister material in Scandinavian high-level nuclear waste disposal program, including the thermodynamics and kinetics of the reactions that are predicted to occur in the practical system have been studied. A comprehensive thermodynamic study of copper in contact with granitic groundwater of the type and composition that is expected in the Forsmark repository in Sweden has been performed. Our primary objective was to ascertain whether copper would exist in the thermodynamically immune state in the repository, in which case corrosion could not occur and the issue of corrosion in the assessment of the storage technology would be moot. In spite of the fact that metallic copper has been found to exist for geological times in granitic geological formations, copper is well-known to be activated from the immune state to corrode by specific species that may exist in the environment. The principal activator of copper is known to be sulfur in its various forms, including sulfide (H2S, HS-, S2-), polysulfide (H2Sx, HSx -, Sx 2-), poly sulfur thiosulfate ( SxO3 2-), and polythionates (SxO6 2-). A comprehensive study of this aspect of copper chemistry has never been reported, and yet an understanding of this issue is vital for assessing whether copper is a suitable material for fabricating canisters for the disposal of HLNW. Our study identifies and explores those species that activate copper; these species include sulfur-containing entities as well as other, non-sulfur species that may be present in the repository. The effects of temperature, solution pH, and hydrogen pressure on the kinetics of the hydrogen electrode reaction (HER) on copper in borate buffer solution have been studied by means of steady-state polarization measurements, including electrochemical impedance spectroscopy (EIS). In order to obtain electrokinetic parameters, such as the exchange current density and the

  11. Colour schemes

    DEFF Research Database (Denmark)

    van Leeuwen, Theo

    2013-01-01

    This chapter presents a framework for analysing colour schemes based on a parametric approach that includes not only hue, value and saturation, but also purity, transparency, luminosity, luminescence, lustre, modulation and differentiation.......This chapter presents a framework for analysing colour schemes based on a parametric approach that includes not only hue, value and saturation, but also purity, transparency, luminosity, luminescence, lustre, modulation and differentiation....

  12. Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    Boatner, L.A.; Sales, B.C.

    1989-01-01

    This patent describes lead-iron phosphate glasses containing a high level of Fe 2 O 3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90 0 C, with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10 2 to 10 3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe 2 O 3 in forming the lead-iron phosphate glass is critical. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms

  13. Management of high level nuclear waste - the nordic approach

    International Nuclear Information System (INIS)

    Engstrom, S.; Aikas, T.

    2000-01-01

    Both the Swedish and the Finnish nuclear waste programmes are aimed at disposal of encapsulated spent nuclear fuel into the crystalline bedrock. In both countries research and development work have been performed since the 1970's. The focus of the programme in both countries is now shifting to practical demonstration of encapsulation technology. In parallel a site-selection programme is being carried out. Finland has selected a site at Eurajoki and is currently waiting for the Government to agree to the choice of the site. In Sweden, at least two sites will be selected by year 2001 with the goal, after performed drillings, to select one of them around 2008. Site selection for the deep repository is probably the most difficult and most sensitive part of the whole programme. The repository will be sited at a suitable place in Sweden respectively Finland where high safety requirements will be met with the consent of the concerned municipality. If there is a Nordic approach to tackle this issue that would probably be: - A stepwise approach in which the disposal is implemented in gradually each step having a decision making stage leading to a commitment of various parties involved to the following stage. -A total transparency of the work performed and the decision making process. - A genuine will from the industry to establish a dialogue with the public in the involved communities. - A will to take the time and the patience necessary to establish a constructive working relationship with the communities participating in the site selection. (authors)

  14. Nuclear developments at the international inter govern mental level (1961)

    International Nuclear Information System (INIS)

    Waynbaum, M.

    1961-01-01

    The United Nations organisation and nuclear energy rose simultaneously, in 1945, to occupy an important place in the public eye. The spiritual succession of the League of Nations which had foundered during the war was taken up by the new organisation which sought to implant its political ideal in a more tangible reality, so that it might thereby be inspired by concrete and substantial objectives. This is one of the reasons for the existence of the dozen specialized agencies created by the family of the United Nations and dealing with Health, Culture, Agriculture, Finance, etc. Nuclear energy is one of these techniques. Becoming suddenly an important power factor and exploiting for itself the prestige of Science, it became the favorite domain for the growth of this new spirit, as much in its universal form in 1945 as in its more regional form which it was later to adopt. The achievements are numerous and of varying importance; they deserve te be studied carefully. (author) [fr

  15. Determination of leveled costs of electric generation for gas plants, coal and nuclear

    International Nuclear Information System (INIS)

    Alonso V, G.; Palacios H, J.C.; Ramirez S, J.R.; Gomez, A.

    2005-01-01

    The present work analyzes the leveled costs of electric generation for different types of nuclear reactors known as Generation III, these costs are compared with the leveled costs of electric generation of plants with the help of natural gas and coal. In the study several discount rates were used to determine their impact in the initial investment. The obtained results are comparable with similar studies and they show that it has more than enough the base of the leveled cost the nuclear option it is quite competitive in Mexico. Also in this study it is also thinks about the economic viability of a new nuclear power station in Mexico. (Author)

  16. Energy level schemes of f{sup N} electronic configurations for the di-, tri-, and tetravalent lanthanides and actinides in a free state

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C.-G. [College of Sciences, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China); Brik, M.G., E-mail: mikhail.brik@ut.ee [College of Sciences, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China); Institute of Physics, University of Tartu, Ravila 14C, Tartu 50411 (Estonia); Institute of Physics, Jan Dlugosz University, Armii Krajowej 13/15, PL-42200 Czestochowa (Poland); Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Liu, D.-X.; Feng, B.; Tian, Ya [College of Sciences, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China); Suchocki, A. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland)

    2016-02-15

    The energy level diagrams are theoretically constructed for the di-, tri-, tetravalent lanthanide and actinide ions, using the Hartree–Fock calculated parameters of the Coulomb and spin–orbit interactions within f{sup N} (N=1…13) electron configurations. These diagrams are analogous to Dieke's diagram, which was obtained experimentally. They can be used for an analysis of the optical spectra of all considered groups of ions in various environments. Systematic variation of some prominent energy levels (especially those ones with a potential for emission transitions) along the isoelectronic 4f/5f ions is considered. - Highlights: • Energy level schemes for di-, tri, tetravalent lanthanides/actinides are calculated. • Systematic variation of the characteristic energy levels across the series is considered. • Potentially interesting emission transitions are identified.

  17. Process for solidifying high-level nuclear waste

    Science.gov (United States)

    Ross, Wayne A.

    1978-01-01

    The addition of a small amount of reducing agent to a mixture of a high-level radioactive waste calcine and glass frit before the mixture is melted will produce a more homogeneous glass which is leach-resistant and suitable for long-term storage of high-level radioactive waste products.

  18. Architecture-Level Exploration of Alternative Interconnection Schemes Targeting 3D FPGAs: A Software-Supported Methodology

    Directory of Open Access Journals (Sweden)

    Kostas Siozios

    2008-01-01

    Full Text Available In current reconfigurable architectures, the interconnection structures increasingly contribute more to the delay and power consumption. The demand for increased clock frequencies and logic density (smaller area footprint makes the problem even more important. Three-dimensional (3D architectures are able to alleviate this problem by accommodating a number of functional layers, each of which might be fabricated in different technology. However, the benefits of such integration technology have not been sufficiently explored yet. In this paper, we propose a software-supported methodology for exploring and evaluating alternative interconnection schemes for 3D FPGAs. In order to support the proposed methodology, three new CAD tools were developed (part of the 3D MEANDER Design Framework. During our exploration, we study the impact of vertical interconnection between functional layers in a number of design parameters. More specifically, the average gains in operation frequency, power consumption, and wirelength are 35%, 32%, and 13%, respectively, compared to existing 2D FPGAs with identical logic resources. Also, we achieve higher utilization ratio for the vertical interconnections compared to existing approaches by 8% for designing 3D FPGAs, leading to cheaper and more reliable devices.

  19. The disposal of high level nuclear waste in the oceans

    International Nuclear Information System (INIS)

    Vilks, Gustavs

    1976-01-01

    A report is given on a meeting held at Woods Hole, Massachusetts to consider the feasibility of using the sea bed as a disposal site for highly radioactive nuclear waste. Some disadvantages are explained, the chief being that ocean water alone, regardless of depth, is a poor barrier. Some delegates discussed emplacement of vitrified waste on the ocean floor, and others its burial in rock or sediment below the floor. The most suitable sites are the mid-plate/mid-gyse localities of abyssal hills. Some engineering work on submarine burial has been done by Sandia Labs., in the U.S.A. Ocean disposal is particularly interesting to Britain and Japan. Data on biological transport rates are needed. (author)

  20. Statistical cluster analysis and diagnosis of nuclear system level performance

    International Nuclear Information System (INIS)

    Teichmann, T.; Levine, M.M.; Samanta, P.K.; Kato, W.Y.

    1985-01-01

    The complexity of individual nuclear power plants and the importance of maintaining reliable and safe operations makes it desirable to complement the deterministic analyses of these plants by corresponding statistical surveys and diagnoses. Based on such investigations, one can then explore, statistically, the anticipation, prevention, and when necessary, the control of such failures and malfunctions. This paper, and the accompanying one by Samanta et al., describe some of the initial steps in exploring the feasibility of setting up such a program on an integrated and global (industry-wide) basis. The conceptual statistical and data framework was originally outlined in BNL/NUREG-51609, NUREG/CR-3026, and the present work aims at showing how some important elements might be implemented in a practical way (albeit using hypothetical or simulated data)

  1. Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    Murphy, W.M.; Kovach, L.A.

    1995-01-01

    A workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste (HLW) was held in San Antonio, Texas, on July 22-25, 1991. It was sponsored by the US Nuclear Regulatory Commission (NRC) and the Center for Nuclear Waste Regulatory Analyses (CNWRA). Invitations to the workshop were extended to a large number of individuals with a variety of technical and professional interests related to geologic disposal of nuclear waste and natural analog studies. The objective of the workshop was to examine the role of natural analog studies in performance assessment, site characterization, and prioritization of research related to geologic disposal of HLW

  2. Nuclear Level Mixing: From a Curiosity to Applications in Nuclear Physics, Solid State Physics and Gamma Optics

    International Nuclear Information System (INIS)

    Neyens, Gerda

    2001-01-01

    The history of 'Nuclear Level Mixing' is closely related to the research that Prof. Coussement performed during the last 25 years. In particular, the impact of this quantum mechanical concept on different research fields will be discussed. Without going in detail, we aim to give the reader an idea of how one single concept may lead to different discoveries

  3. Enzymatic versus Inorganic Oxygen Reduction Catalysts: Comparison of the Energy Levels in a Free-Energy Scheme

    DEFF Research Database (Denmark)

    Kjærgaard, Christian Hauge; Rossmeisl, Jan; Nørskov, Jens Kehlet

    2010-01-01

    In this paper, we present a method to directly compare the energy levels of intermediates in enzymatic and inorganic oxygen reduction catalysts. We initially describe how the energy levels of a Pt(111) catalyst, operating at pH = 0, are obtained. By a simple procedure, we then convert the energy...... levels of cytochrome c oxidase (CcO) models obtained at physiological pH = 7 to the energy levels at pH = 0, which allows for comparison. Furthermore, we illustrate how different bias voltages will affect the free-energy landscapes of the catalysts. This allows us to determine the so-called theoretical...

  4. Fluctuation properties of nuclear energy levels and widths: comparison of theory with experiment

    International Nuclear Information System (INIS)

    Bohigas, O.; Haq, R.U.; Pandey, A.

    1982-09-01

    We analyze the fluctuation properties of nuclear energy levels and widths with new spectrally averaged measures. A remarkably close agreement between the predictions of random-matrix theories and experiment is found

  5. Threshold Signature Schemes Application

    Directory of Open Access Journals (Sweden)

    Anastasiya Victorovna Beresneva

    2015-10-01

    Full Text Available This work is devoted to an investigation of threshold signature schemes. The systematization of the threshold signature schemes was done, cryptographic constructions based on interpolation Lagrange polynomial, elliptic curves and bilinear pairings were examined. Different methods of generation and verification of threshold signatures were explored, the availability of practical usage of threshold schemes in mobile agents, Internet banking and e-currency was shown. The topics of further investigation were given and it could reduce a level of counterfeit electronic documents signed by a group of users.

  6. Low-level radon measurements by nuclear track detectors

    International Nuclear Information System (INIS)

    Koksal, E. M.; Goksel, S. A.; Alkan, H.

    1985-01-01

    In the work to be described here we have developed a passive nuclear track dosimeter to measure the integrated value of indoor radon (Rn-222) over a long period of time. Passive radon dosimeter which we have developed in our laboratories makes use of two small pieces of CR-39 plastic (Allyl diglycol carbonate) as detectors for registering tracks of alpha particles emitted by radon. These CR-39 plastic detectors are fixed on the inside bottom of a cup-shaped polystrene enclosure which is closed at the top by a tissue permeable for gases only. CR-39 detectors exposed to radon gas in the indoor air for a period of six months then are removed and chemically etched to make the alpha particle tracks visible under the microscope. The counts of tracks are evaluated to determine the radon concentration in the air in comparison with the number of tracks produced by a known concentration of radon gas. By using the passive dosimeters developed and the chemical etching procedure descriped here, measurements of indoor radon concentrations were carried out in 45 houses in different districts of the city of Istanbul. In this pilot experiment mean radon concentrations between 0.7 and 3.5 pCi/l have been found in these houses. In order to improve the counting of alpha tracks produced on the detectors a prototype electrochemical etching system in addition to chemical etching, is being developed. (author)

  7. Method for accounting for γ-γ-coincidences in compu-- ter reconstruction of energy level and γ-transition schemes

    International Nuclear Information System (INIS)

    Burmistrov, V.R.

    1979-01-01

    The principle and program of introduction of data on γ-γ- coincidences into the computer program are described. By analogy with the principle of accounting for γ-line intensities while constructing a system of levels according to the reference levels and γ-line spectrum, the ''leaving'' γ-transitions are introduced as an artificial level parameter. This parameter is a list of γ-lines leaving the given level or the lower levels bound with it. As a result of introducing such parameters, the accounting for the data on γ-γ-coincidences amounts to comparing two tables of numbers: a table of γ-line coincidences (an experimental one) and a table of ''leaving'' γ-transitions of every level. The program arranges the γ-lines in the preset system of equations with regard to the γ-line energies, their intensities and data on γ-γ- coincidences, and excludes consideration of the false levels. The calculation results are printed out in tables [ru

  8. A CU-Level Rate and Distortion Estimation Scheme for RDO of Hardware-Friendly HEVC Encoders Using Low-Complexity Integer DCTs.

    Science.gov (United States)

    Lee, Bumshik; Kim, Munchurl

    2016-08-01

    In this paper, a low complexity coding unit (CU)-level rate and distortion estimation scheme is proposed for High Efficiency Video Coding (HEVC) hardware-friendly implementation where a Walsh-Hadamard transform (WHT)-based low-complexity integer discrete cosine transform (DCT) is employed for distortion estimation. Since HEVC adopts quadtree structures of coding blocks with hierarchical coding depths, it becomes more difficult to estimate accurate rate and distortion values without actually performing transform, quantization, inverse transform, de-quantization, and entropy coding. Furthermore, DCT for rate-distortion optimization (RDO) is computationally high, because it requires a number of multiplication and addition operations for various transform block sizes of 4-, 8-, 16-, and 32-orders and requires recursive computations to decide the optimal depths of CU or transform unit. Therefore, full RDO-based encoding is highly complex, especially for low-power implementation of HEVC encoders. In this paper, a rate and distortion estimation scheme is proposed in CU levels based on a low-complexity integer DCT that can be computed in terms of WHT whose coefficients are produced in prediction stages. For rate and distortion estimation in CU levels, two orthogonal matrices of 4×4 and 8×8 , which are applied to WHT that are newly designed in a butterfly structure only with addition and shift operations. By applying the integer DCT based on the WHT and newly designed transforms in each CU block, the texture rate can precisely be estimated after quantization using the number of non-zero quantized coefficients and the distortion can also be precisely estimated in transform domain without de-quantization and inverse transform required. In addition, a non-texture rate estimation is proposed by using a pseudoentropy code to obtain accurate total rate estimates. The proposed rate and the distortion estimation scheme can effectively be used for HW-friendly implementation of

  9. Examination of the Current Approaches to State-Level Nuclear Security Evaluation

    International Nuclear Information System (INIS)

    Kim, Chan; Yim, Mansung; Kim, So Young

    2014-01-01

    An effective global nuclear materials security system will cover all materials, employ international standards and best practices, and reduce risks by reducing weapons-usable nuclear material stocks and the number of locations where they are found. Such a system must also encourage states to accept peer reviews by outside experts in order to demonstrate that effective security is in place. It is thus critically important to create an integrative framework of state-level evaluation of nuclear security as a basis for measuring the level and progress of international effort to secure and control all nuclear materials. There have been studies to represent state-level nuclear security with a quantitative metric. A prime example is the Nuclear Materials Security Index (NMSI) by the Nuclear Threat Initiative (NTI). Another comprehensive study is the State Level Risk Metric by Texas A and M University (TAMU). This paper examines the current methods with respect to their strengths and weaknesses and identifies the directions for future research to improve upon the existing approaches

  10. Developing Curriculum of Nuclear Civil Engineering Degree Programme at Graduate Level

    International Nuclear Information System (INIS)

    Iqbal, J.

    2016-01-01

    Full text: The paper suggests the introduction of a new degree, namely nuclear civil engineering at graduate level for better utilization of civil engineers in nuclear power plant (NPP) design and construction. At present, both nuclear engineering and civil engineering degrees are offered at undergraduate and graduate levels in numerous renowned universities of the world. However, when a civil engineer, even after completion of nuclear engineering at postgraduate level, undertakes an assignment related to NPP design, he comes across various problems which are not covered in the present curricula. For instance, NPPs’ siting issues, design of pre-stressed concrete containment against loads of loss of coolant accident (LOCA), various impulsive and impactive loads (e.g., detonations, aircraft crash analysis, etc.) and shielding calculations are some of the core issues during nuclear power plant design. The paper highlights the importance of introduction of nuclear civil engineering degree at the graduate level. Besides, the contents of the proposed course work have also been discussed. Keeping in view the fact that, currently, no such degree is offered in any university of the world, the paper explores useful avenues to human resource development for introducing and expanding nuclear power programmes. (author

  11. Application of smart transmitter technology in nuclear engineering measurements with level detection algorithm

    International Nuclear Information System (INIS)

    Kang, Hyun Gook; Seong, Poong Hyun

    1994-01-01

    In this study a programmable smart transmitter is designed and applied to the nuclear engineering measurements. In order to apply the smart transmitter technology to nuclear engineering measurements, the water level detection function is developed and applied in this work. In the real time system, the application of level detection algorithm can make the operator of the nuclear power plant sense the water level more rapidly. Furthermore this work can simplify the data communication between the level-sensing thermocouples and the main signal processor because the level signal is determined at field. The water level detection function reduces the detection time to about 8.3 seconds by processing the signal which has the time constant 250 seconds and the heavy noise signal

  12. The management-retrieval code of nuclear level density sub-library (CENPL-NLD)

    International Nuclear Information System (INIS)

    Ge Zhigang; Su Zongdi; Huang Zhongfu; Dong Liaoyuan

    1995-01-01

    The management-retrieval code of the Nuclear Level Density (NLD) is presented. It contains two retrieval ways: single nucleus (SN) and neutron reaction (NR). The latter contains four kinds of retrieval types. This code not only can retrieve level density parameter and the data related to the level density, but also can calculate the relevant data by using different level density parameters and do comparison of the calculated results with related data in order to help user to select level density parameters

  13. 76 FR 35137 - Vulnerability and Threat Information for Facilities Storing Spent Nuclear Fuel and High-Level...

    Science.gov (United States)

    2011-06-16

    ... High-Level Radioactive Waste AGENCY: U.S. Nuclear Regulatory Commission. ACTION: Public meeting... Nuclear Fuel, High-Level Radioactive Waste, and Reactor-Related Greater Than Class C Waste,'' and 73... Spent Nuclear Fuel (SNF) and High-Level Radioactive Waste (HLW) storage facilities. The draft regulatory...

  14. Reactor waste heat utilization and district heating reactors. Nuclear district heating in Sweden - Regional reject heat utilization schemes and small heat-only reactors

    International Nuclear Information System (INIS)

    Hannerz, K.; Larsson, Y.; Margen, P.

    1977-01-01

    A brief review is given of the current status of district heating in Sweden. In future, district heating schemes will become increasingly interesting as a means of utilizing heat from nuclear reactors. Present recommendations in Sweden are that large reactors should not be located closer than about 20 km from large population centres. Reject heat from such reactors is cheap at source. To minimize the cost of long distance hot water transmission large heat rates must be transmitted. Only areas with large populations can meet this requirement. The three areas of main interest are Malmoe/Lund/Helsingborg housing close to 0.5 million; Greater Stockholm housing 1 to 1.5 million and Greater Gothenburg housing about 0.5 million people. There is an active proposal that the Malmoe/Lund/Helsingborg region would be served by a third nuclear unit at Barsebaeck, located about 20 km from Malmoe/Lund and supplying 950 MW of base load heat. Preliminary proposals for Stockholm involve a 2000 MW heat supply; proposals for Gothenburg are more tentative. The paper describes progress on these proposals and their technology. It also outlines technology under development to increase the economic range of large scale heat transport and to make distribution economic even for low heat-density family housing estates. Regions apart from the few major urban areas mentioned above require the adoption of a different approach. To this end the development of a small, simple low-temperature reactor for heat-only production suitable for urban location has been started in Sweden in close contact with Finland. Some results of the work in progress are presented, with emphasis on the safety requirements. An outline is given in the paper as to how problems of regional heat planning and institutional and legislative issues are being approached

  15. Exploring patient satisfaction levels, self-rated oral health status and associated variables among citizens covered for dental insurance through a National Social Security Scheme in India.

    Science.gov (United States)

    Singh, Abhinav; Purohit, Bharathi M

    2017-06-01

    To assess patient satisfaction, self-rated oral health and associated factors, including periodontal status and dental caries, among patients covered for dental insurance through a National Social Security Scheme in New Delhi, India. A total of 1,498 patients participated in the study. Satisfaction levels and self-rated oral-health scores were measured using a questionnaire comprising 12 closed-ended questions. Clinical data were collected using the Community Periodontal Index (CPI) and the decayed, missing and filled teeth (DMFT) index. Regression analysis was conducted to evaluate factors associated with dental caries, periodontal status and self-rated oral health. Areas of concern included poor cleanliness within the hospital, extensive delays for appointments, waiting time in hospital and inadequate interpersonal and communication skills among health-care professionals. Approximately 51% of the respondents rated their oral health as fair to poor. Younger age, no tobacco usage, good periodontal status and absence of dental caries were significantly associated with higher oral health satisfaction, with odds ratios of 3.94, 2.38, 2.58 and 2.09, respectively (P ≤ 0.001). The study indicates poor satisfaction levels with the current dental care system and a poor self-rated oral health status among the study population. Some specific areas of concern have been identified. These findings may facilitate restructuring of the existing dental services under the National Social Security Scheme towards creating a better patient care system. © 2017 FDI World Dental Federation.

  16. Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Clarno, Kevin T [ORNL; Hamilton, Steven P [ORNL; Philip, Bobby [ORNL; Berrill, Mark A [ORNL; Sampath, Rahul S [ORNL; Allu, Srikanth [ORNL; Pugmire, Dave [ORNL; Dilts, Gary [Los Alamos National Laboratory (LANL); Banfield, James E [ORNL

    2012-02-01

    The Advanced Multi-Physics (AMP) Nuclear Fuel Performance code (AMPFuel) is focused on predicting the temperature and strain within a nuclear fuel assembly to evaluate the performance and safety of existing and advanced nuclear fuel bundles within existing and advanced nuclear reactors. AMPFuel was extended to include an integrated nuclear fuel assembly capability for (one-way) coupled radiation transport and nuclear fuel assembly thermo-mechanics. This capability is the initial step toward incorporating an improved predictive nuclear fuel assembly modeling capability to accurately account for source-terms and boundary conditions of traditional (single-pin) nuclear fuel performance simulation, such as the neutron flux distribution, coolant conditions, and assembly mechanical stresses. A novel scheme is introduced for transferring the power distribution from the Scale/Denovo (Denovo) radiation transport code (structured, Cartesian mesh with smeared materials within each cell) to AMPFuel (unstructured, hexagonal mesh with a single material within each cell), allowing the use of a relatively coarse spatial mesh (10 million elements) for the radiation transport and a fine spatial mesh (3.3 billion elements) for thermo-mechanics with very little loss of accuracy. In addition, a new nuclear fuel-specific preconditioner was developed to account for the high aspect ratio of each fuel pin (12 feet axially, but 1 4 inches in diameter) with many individual fuel regions (pellets). With this novel capability, AMPFuel was used to model an entire 17 17 pressurized water reactor fuel assembly with many of the features resolved in three dimensions (for thermo-mechanics and/or neutronics), including the fuel, gap, and cladding of each of the 264 fuel pins; the 25 guide tubes; the top and bottom structural regions; and the upper and lower (neutron) reflector regions. The final, full assembly calculation was executed on Jaguar using 40,000 cores in under 10 hours to model over 162

  17. Status of the French nuclear high level waste disposal

    International Nuclear Information System (INIS)

    Sombret, C.

    1985-09-01

    French research on high level waste processing has led to the development of industrial vitrification facilities. Borosilicate glass is still being investigated for its long-term storage properties, since it is itself a component of the containment system. The other constituents of this system, the engineered barriers, are also being actively investigated. The geological barrier is now being assessed using a methodology applicable to various types of geological formations, and final site qualification should be possible before the end of 1992

  18. Intervention levels for protective measures in nuclear accidents

    International Nuclear Information System (INIS)

    Hedemann Jensen, P.

    1992-12-01

    A radiation protection philosophy for exposure situations following an accident has been developed by international organisations such as the ICRP, IAEA, NES/OECD, FAO/WHO, and the CEC during the last decade. After the Chernobyl accident, the application of radiation protection principles for intervention situations such as exposure from accidental contamination or radon in dwellings were further developed and this work is still in progress. The present intervention policy recommended by the international organisations as well as by the Nordic radiation protection authorities is reviewed. The Nordic Intervention levels for foodstuff restrictions, both for the Chernobyl and post-Chernobyl periods, have been based on dose limits and they are therefore in conflict with international intervention policy. Illustrative examples on intervention level setting for relocation and foodstuff restrictions are derived for Nordic conditions from the optimisation principle recommended by the international organisations. Optimised Generic Intervention Levels have been determined to be about 10 mSv x month -1 for relocation/return and 5,000-30,000 Bqxkg -1 for restrictions on various foodstuffs contaminated with 137 Cs and 131 I. (au) (14 tabs., 1 ill., 16 refs.)

  19. Tradable schemes

    NARCIS (Netherlands)

    J.K. Hoogland (Jiri); C.D.D. Neumann

    2000-01-01

    textabstractIn this article we present a new approach to the numerical valuation of derivative securities. The method is based on our previous work where we formulated the theory of pricing in terms of tradables. The basic idea is to fit a finite difference scheme to exact solutions of the pricing

  20. Recoupling and decoupling of nuclear spin interactions at high MAS frequencies: numerical design of CNnν symmetry-based RF pulse schemes

    International Nuclear Information System (INIS)

    Herbst, Christian; Herbst, Jirada; Kirschstein, Anika; Leppert, Joerg; Ohlenschlaeger, Oliver; Goerlach, Matthias; Ramachandran, Ramadurai

    2009-01-01

    The CN n ν class of RF pulse schemes, commonly employed for recoupling and decoupling of nuclear spin interactions in magic angle spinning solid state NMR studies of biological systems, involves the application of a basic 'C' element corresponding to an RF cycle with unity propagator. In this study, the design of CN n ν symmetry-based RF pulse sequences for achieving 13 C- 13 C double-quantum dipolar recoupling and through bond scalar coupling mediated 13 C- 13 C chemical shift correlation has been examined at high MAS frequencies employing broadband, constant-amplitude, phase-modulated basic 'C' elements. The basic elements were implemented as a sandwich of a small number of short pulses of equal duration with each pulse characterised by an RF phase value. The phase-modulation profile of the 'C' element was optimised numerically so as to generate efficient RF pulse sequences. The performances of the sequences were evaluated via numerical simulations and experimental measurements and are presented here

  1. The development of a speech act coding scheme to characterize communication patterns under an off-normal situation in nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Seung Hwan; Park, Jin Kyun

    2009-01-01

    Since communication is an important means to exchange information between individuals/teams or auxiliary means to share resources and information given in the team and group activity, effective communication is the prerequisite for construct powerful teamwork by a sharing mental model. Therefore, unless communication is performed efficiently, the quality of task and performance of team lower. Furthermore, since communication is highly related to situation awareness during team activities, inappropriate communication causes a lack of situation awareness and tension and stress are intensified and errors are increased. According to lesson learned from several accidents that have actually occurred in nuclear power plant (NPP), consequence of accident leads most critical results and is more dangerous than those of other industries. In order to improve operator's cope ability and operation ability through simulation training with various off-normal condition, the operation groups are trained regularly every 6 months in the training center of reference NPP. The objective of this study is to suggest modified speech act coding scheme and to elucidate the communication pattern characteristics of an operator's conversation during an abnormal situation in NPP

  2. The development of a speech act coding scheme to characterize communication patterns under an off-normal situation in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Hwan; Park, Jin Kyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    Since communication is an important means to exchange information between individuals/teams or auxiliary means to share resources and information given in the team and group activity, effective communication is the prerequisite for construct powerful teamwork by a sharing mental model. Therefore, unless communication is performed efficiently, the quality of task and performance of team lower. Furthermore, since communication is highly related to situation awareness during team activities, inappropriate communication causes a lack of situation awareness and tension and stress are intensified and errors are increased. According to lesson learned from several accidents that have actually occurred in nuclear power plant (NPP), consequence of accident leads most critical results and is more dangerous than those of other industries. In order to improve operator's cope ability and operation ability through simulation training with various off-normal condition, the operation groups are trained regularly every 6 months in the training center of reference NPP. The objective of this study is to suggest modified speech act coding scheme and to elucidate the communication pattern characteristics of an operator's conversation during an abnormal situation in NPP.

  3. Multiple external hazards compound level 3 PSA methods research of nuclear power plant

    Science.gov (United States)

    Wang, Handing; Liang, Xiaoyu; Zhang, Xiaoming; Yang, Jianfeng; Liu, Weidong; Lei, Dina

    2017-01-01

    2011 Fukushima nuclear power plant severe accident was caused by both earthquake and tsunami, which results in large amount of radioactive nuclides release. That accident has caused the radioactive contamination on the surrounding environment. Although this accident probability is extremely small, once such an accident happens that is likely to release a lot of radioactive materials into the environment, and cause radiation contamination. Therefore, studying accidents consequences is important and essential to improve nuclear power plant design and management. Level 3 PSA methods of nuclear power plant can be used to analyze radiological consequences, and quantify risk to the public health effects around nuclear power plants. Based on multiple external hazards compound level 3 PSA methods studies of nuclear power plant, and the description of the multiple external hazards compound level 3 PSA technology roadmap and important technical elements, as well as taking a coastal nuclear power plant as the reference site, we analyzed the impact of off-site consequences of nuclear power plant severe accidents caused by multiple external hazards. At last we discussed the impact of off-site consequences probabilistic risk studies and its applications under multiple external hazards compound conditions, and explained feasibility and reasonableness of emergency plans implementation.

  4. Low-lying nuclear levels and radiative transitions in hadronic atoms

    International Nuclear Information System (INIS)

    Popov, V.S.; Kudryavtsev, A.E.; Lisin, V.I.; Mur, V.D.

    1985-01-01

    The analytic theory of nuclear level shifts permit the position of the nuclear level perturbing the Coulomb spectrum to be calculated on the basis of the magnitude of the level shift of a hadron atom. As an example the K -4 He atom is discussed. The experimental data on the 2p-level shift indicate that a weakly bound p-state with a binding energy and width epsilon approximately γ approximately 0.5 MeV may exist in the system. The probabilities for radiative transitions to this level and the cross section for its creation in a nuclear reaction with 6 Li are calculated. The possible existence of weakly coupled K - and anti p states for other light nuclei is discussed. An exact solution of the model Coulomb problem with short range interaction is obtained and this permits the limits of validity of the initial approximations to be determined

  5. Control scheme of three-level H-bridge converter for interfacing between renewable energy resources and AC grid

    DEFF Research Database (Denmark)

    Pouresmaeil, Edris; Montesinos-Miracle, Daniel; Gomis-Bellmunt, Oriol

    2011-01-01

    This paper presents a control strategy of multilevel converters for integration of renewable energy resources into power grid. The proposed technique provides compensation for active, reactive, and harmonic current components of grid-connected loads. A three-level H-bridge converter is proposed a...

  6. Level-1 Data Driver Card of the ATLAS New Small Wheel upgrade compatible with the Phase II 1 MHz readout scheme

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00549793; The ATLAS collaboration

    2016-01-01

    The Level-1 Data Driver Card (L1DDC) will be designed for the needs of the future upgrades of the innermost stations of the ATLAS end-cap muon spectrometer. The L1DDC is a high speed aggregator board capable of communicating with a large number of front-end electronics. It collects the Level-1 data along with monitoring data and transmits them to a network interface through a single bidirectional fiber link. In addition, the L1DDC board distributes trigger, time and configuration data coming from the network interface to the front-end boards. The L1DDC is fully compatible with the Phase II upgrade where the trigger rate is expected to reach 1 MHz. This paper describes the overall scheme of the data acquisition process and especially the three different L1DDC boards that will be fabricated. Moreover the L1DDC prototype-1 is also described.

  7. Nuclear power plant personnel entry level qualifications and training

    International Nuclear Information System (INIS)

    Jorgensen, C.C.; Haas, P.M.; Selby, D.L.; Lowry, J.C.

    1983-01-01

    This paper summarizes the early results and current status of a research program at ORNL which is intended to provide the methods and technical basis for NRC to initiate the use of the Systems Approach to Training (SAT) in the evaluation of training programs and entry level qualifications for NPP control room personnel. The program is an outgrowth of previous studies of simulator hardware and simulator training requirements under the Safety Related Operator Actions Program which recommended adaptation of a systems methodology to development and evaluation of NPP training programs

  8. Evaluation of regional-scale water level simulations using various river routing schemes within a hydrometeorological modelling framework for the preparation of the SWOT mission

    Science.gov (United States)

    Häfliger, V.; Martin, E.; Boone, A. A.; Habets, F.; David, C. H.; Garambois, P. A.; Roux, H.; Ricci, S. M.; Thévenin, A.; Berthon, L.; Biancamaria, S.

    2014-12-01

    The ability of a regional hydrometeorological model to simulate water depth is assessed in order to prepare for the SWOT (Surface Water and Ocean Topography) mission that will observe free surface water elevations for rivers having a width larger than 50/100 m. The Garonne river (56 000 km2, in south-western France) has been selected owing to the availability of operational gauges, and the fact that different modeling platforms, the hydrometeorological model SAFRAN-ISBA-MODCOU and several fine scale hydraulic models, have been extensively evaluated over two reaches of the river. Several routing schemes, ranging from the simple Muskingum method to time-variable parameter kinematic and diffusive waves schemes with time varying parameters, are tested using predetermined hydraulic parameters. The results show that the variable flow velocity scheme is advantageous for discharge computations when compared to the original Muskingum routing method. Additionally, comparisons between water level computations and in situ observations led to root mean square errors of 50-60 cm for the improved Muskingum method and 40-50 cm for the kinematic-diffusive wave method, in the downstream Garonne river. The error is larger than the anticipated SWOT resolution, showing the potential of the mission to improve knowledge of the continental water cycle. Discharge computations are also shown to be comparable to those obtained with high-resolution hydraulic models over two reaches. However, due to the high variability of river parameters (e.g. slope and river width), a robust averaging method is needed to compare the hydraulic model outputs and the regional model. Sensitivity tests are finally performed in order to have a better understanding of the mechanisms which control the key hydrological processes. The results give valuable information about the linearity, Gaussianity and symetry of the model, in order to prepare the assimilation of river heights in the model.

  9. Siting high-level nuclear waste repositories: A progress report for Rhode Island

    International Nuclear Information System (INIS)

    Frohlich, R.K.; Vild, B.F.

    1986-03-01

    In this booklet, we will not try to argue the pros and cons of nuclear power or weapons production. We will focus instead on the issue of nuclear waste disposal. With the passage of the Nuclear Waste Policy Act (NWPA) of 1982, the US Congress and the President charged federal and state regulators with the responsibility of settling that issue by the end of this century - with extensive public involvement. This booklet, now in its second printing, is designed to explain the nature of ''high-level'' nuclear waste, the essential criteria for its safe and permanent disposal, and Rhode Island's participation in the federal repository program. It has been funded from a USDOE grant derived from a utility-financed Nuclear Waste Fund established under the NWPA. 17 refs., 10 figs., 2 tabs

  10. Safe immobilization of high-level nuclear reactor wastes

    International Nuclear Information System (INIS)

    Ringwood, A.; Kesson, S.; Ware, N.; Hibberson, W.; Major, A.

    1979-01-01

    The advantages and disadvantages of methods of immobilizing high-level radioactive wastes are discussed. Problems include the devitrification of glasses and the occurrence of radiation damage. An alternative method of radioctive waste immobilization is described in which the waste is incorporated in the constituent minerals of a synthetic rock, Synroc. Synroc is immune from devitrification and is composed of phases which possess crystal structures identical to those of minerals which are known to have retained radioactive elements in geological environments at elevated pressures and tempertures for long periods. The composition and mineralogy of Synroc is given and the process of immobilizing wastes in Synroc is described. Accelerated leaching tests at elevated pressures and temperatures are also described

  11. Concrete conditioners for low-intermediate level nuclear wastes

    International Nuclear Information System (INIS)

    Roehl, J.L.; Lorentz, R.G.; Franzen, H.R.

    1986-01-01

    The conditioning of low-intermediate level radioactive waste disposal, in Brazil, with concrete packages designed in such way that, in spite of being destined to receive compacted materials in long term sub-surface disposal, they may also be able to attend other storage or disposal necessities, is analysed. A design of a reinforced concrete package with a net volume of 360 l and, with compatible diameter to contain compacted 200 l drums, was developed. A study on compactation of 200 l steel packages is done. A pressure of 30.000 KN for compacting these 200 l drums was adapted, and two series of tests to verify the pressure volume reduction ratio and, the final dimensions and density of the compacted elements, was executed. (Author) [pt

  12. Nuclear Regulatory Commission low-level radioactive waste management program

    International Nuclear Information System (INIS)

    1977-09-01

    It is believed that the priorities of NRC work in low-level waste management as described in this action plan are consistent with the needs of the overall national waste management program. Present licensing procedures and criteria are adequate for the short term, and priority attention is being given to the longer term, when the quantities of waste to be managed will be greater and licensing demand will increase. The plan makes use of expertise within NRC to achieve early results and is coordinated with other Federal agencies having related responsibilities. Since NRC decisions will affect industry, other governmental jurisdictions, private interest groups, and the public at large, procedures were developed to involve them in planning the program

  13. Nuclear decay scheme studies of 30-h 131Te/sup m/, 25-min 131Te/sup g/, and 55.5-min 105Cd

    International Nuclear Information System (INIS)

    Jackson, S.V.

    1975-01-01

    High-resolution Ge(Li) detectors have been used to observe γ-ray singles and coincidence spectra of 30-h 11 / 2 - , /sup 131m/Te, 25-min 3 / 2 + , and 55.5-min 5 / 2 + 105 Cd. Sources of /sup 131m/Te and /sup 131g/Te were produced by neutron irradiation of enriched 130 Te metal, and, in the case of /sup 131m/Te, were chemically purified to remove the 131 I daughter. A total of 190 and 80 γ-rays are attributed to the decays of /sup 131m/Te and /sup 131g/Te, respectively; and 174 and 77 of these transitions have been placed in a 131 I level scheme involving 52 excited states. Absolute β group intensities were determined for the transitions to 131 I levels. Spin and parity assignments were made for all observed levels. The β feeding from the 11 / 2 - /sup 131m/Te to the 7 / 2 + 131 I ground state was determined to be (5.2 +- 3.0) percent (log ft = 10.5). The isomeric transition of 11 / 2 - /sup 131m/Te to 3 / 2 + /sup 131g/Te was determined to be (22.2 +- 1.6) percent. The 6-nsec isomer in 131 I at 1797 keV has been assigned as 15 / 2 - and interpreted as a πν 1 ν 2 three quasi-particle state. Sources of 105 Cd were produced via the 106 Cd(n,2n) reaction on enriched 106 CdO using 14 MeV neutrons. A total of 274 γ-rays are attributed to the decay of 105 Cd, and 248 of these have been placed in a 105 Ag level scheme involving 50 excited states. Absolute values for the β + /EC transition intensities to 105 Ag levels were determined. The β + /EC feeding from the 5 / 2 + 105 Cd to the 7 / 2 + 25.5-keV isomeric state in 105 Ag was determined to be (51.4 +- 4.0) percent (log ft = 5.4). The experimentally determined level structures of 131 I and 105 Cd are interpreted in terms of the shell model and core excitation considerations with emphasis placed on the core coupling model and the three-particle models. (U.S.)

  14. Nuclear Level Densities for Modeling Nuclear Reactions: An Efficient Approach Using Statistical Spectroscopy

    International Nuclear Information System (INIS)

    Calvin W. Johnson

    2005-01-01

    The general goal of the project is to develop and implement computer codes and input files to compute nuclear densities of state. Such densities are important input into calculations of statistical neutron capture, and are difficult to access experimentally. In particular, we will focus on calculating densities for nuclides in the mass range A ∼ 50-100. We use statistical spectroscopy, a moments method based upon a microscopic framework, the interacting shell model. Second year goals and milestones: Develop two or three competing interactions (based upon surface-delta, Gogny, and NN-scattering) suitable for application to nuclei up to A = 100. Begin calculations for nuclides with A = 50-70

  15. Using Direct Sub-Level Entity Access to Improve Nuclear Stockpile Simulation Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Robert Y. [Brigham Young Univ., Provo, UT (United States)

    1999-08-01

    Direct sub-level entity access is a seldom-used technique in discrete-event simulation modeling that addresses the accessibility of sub-level entity information. The technique has significant advantages over more common, alternative modeling methods--especially where hierarchical entity structures are modeled. As such, direct sub-level entity access is often preferable in modeling nuclear stockpile, life-extension issues, an area to which it has not been previously applied. Current nuclear stockpile, life-extension models were demonstrated to benefit greatly from the advantages of direct sub-level entity access. In specific cases, the application of the technique resulted in models that were up to 10 times faster than functionally equivalent models where alternative techniques were applied. Furthermore, specific implementations of direct sub-level entity access were observed to be more flexible, efficient, functional, and scalable than corresponding implementations using common modeling techniques. Common modeling techniques (''unbatch/batch'' and ''attribute-copying'') proved inefficient and cumbersome in handling many nuclear stockpile modeling complexities, including multiple weapon sites, true defect analysis, and large numbers of weapon and subsystem types. While significant effort was required to enable direct sub-level entity access in the nuclear stockpile simulation models, the enhancements were worth the effort--resulting in more efficient, more capable, and more informative models that effectively addressed the complexities of the nuclear stockpile.

  16. CSR schemes in agribusiness

    DEFF Research Database (Denmark)

    Pötz, Katharina Anna; Haas, Rainer; Balzarova, Michaela

    2013-01-01

    of schemes that can be categorized on focus areas, scales, mechanisms, origins, types and commitment levels. Research limitations/implications – The findings contribute to conceptual and empirical research on existing models to compare and analyse CSR standards. Sampling technique and depth of analysis limit......Purpose – The rise of CSR followed a demand for CSR standards and guidelines. In a sector already characterized by a large number of standards, the authors seek to ask what CSR schemes apply to agribusiness, and how they can be systematically compared and analysed. Design....../methodology/approach – Following a deductive-inductive approach the authors develop a model to compare and analyse CSR schemes based on existing studies and on coding qualitative data on 216 CSR schemes. Findings – The authors confirm that CSR standards and guidelines have entered agribusiness and identify a complex landscape...

  17. Cyclic features of the consequences from a postulated nuclear accident: a case study of the third level probabilistic safety assessment

    International Nuclear Information System (INIS)

    Xinhe, LIU; Homma, Toshimitsu

    2002-01-01

    In the third level probabilistic safety assessment, one of the three popular meteorological sequence sampling methods is cyclic sampling. The rationale of cyclic sampling is obviously that cyclic variation is the significant characteristics of the meteorological sequences and the health consequences resulting from a postulated nuclear accident are also remarkably of cyclic features. In this work, a set of time series was established for different health consequences using S3 source term and a whole year meteorological data. OSCAAR software system was utilized in the calculation of the health consequences. It is shown by the analysis that diurnal variation is remarked for all the kinds of health consequences, implying that cyclic sampling would be more effective than random sampling. The results also showed that there are not any dominating frequencies in the spectra of the consequences so that cyclic sampling might be incompetent to reduce the third level PSA to a satisfied level. Therefore, new schemes of meteorological sampling should be developed in the light of consideration of complex coupling of meteorological condition and population distribution rather than the consideration of meteorological condition alone

  18. Evaluation and interconversion of various indicator PCB schemes for ∑PCB and dioxin-like PCB toxic equivalent levels in fish.

    Science.gov (United States)

    Gandhi, Nilima; Bhavsar, Satyendra P; Reiner, Eric J; Chen, Tony; Morse, Dave; Arhonditsis, George B; Drouillard, Ken G

    2015-01-06

    Polychlorinated biphenyls (PCBs) remain chemicals of concern more than three decades after the ban on their production. Technical mixture-based total PCB measurements are unreliable due to weathering and degradation, while detailed full congener specific measurements can be time-consuming and costly for large studies. Measurements using a subset of indicator PCBs (iPCBs) have been considered appropriate; however, inclusion of different PCB congeners in various iPCB schemes makes it challenging to readily compare data. Here, using an extensive data set, we examine the performance of existing iPCB3 (PCB 138, 153, and 180), iPCB6 (iPCB3 plus 28, 52, and 101) and iPCB7 (iPCB6 plus 118) schemes, and new iPCB schemes in estimating total of PCB congeners (∑PCB) and dioxin-like PCB toxic equivalent (dlPCB-TEQ) concentrations in sport fish fillets and the whole body of juvenile fish. The coefficients of determination (R(2)) for regressions conducted using logarithmically transformed data suggest that inclusion of an increased number of PCBs in an iPCB improves relationship with ∑PCB but not dlPCB-TEQs. Overall, novel iPCB3 (PCB 95, 118, and 153), iPCB4 (iPCB3 plus 138) and iPCB5 (iPCB4 plus 110) presented in this study and existing iPCB6 and iPCB7 are the most optimal indicators, while the current iPCB3 should be avoided. Measurement of ∑PCB based on a more detailed analysis (50+ congeners) is also overall a good approach for assessing PCB contamination and to track PCB origin in fish. Relationships among the existing and new iPCB schemes have been presented to facilitate their interconversion. The iPCB6 equiv levels for the 6.5 and 10 pg/g benchmarks of dlPCB-TEQ05 are about 50 and 120 ng/g ww, respectively, which are lower than the corresponding iPCB6 limits of 125 and 300 ng/g ww set by the European Union.

  19. Poverty identification for a pro-poor health insurance scheme in Tanzania: reliability and multi-level stakeholder perceptions.

    Science.gov (United States)

    Kuwawenaruwa, August; Baraka, Jitihada; Ramsey, Kate; Manzi, Fatuma; Bellows, Ben; Borghi, Josephine

    2015-12-01

    Many low income countries have policies to exempt the poor from user charges in public facilities. Reliably identifying the poor is a challenge when implementing such policies. In Tanzania, a scorecard system was established in 2011, within a programme providing free national health insurance fund (NHIF) cards, to identify poor pregnant women and their families, based on eight components. Using a series of reliability tests on a 2012 dataset of 2,621 households in two districts, this study compares household poverty levels using the scorecard, a wealth index, and monthly consumption expenditures. We compared the distributions of the three wealth measures, and the consistency of household poverty classification using cross-tabulations and the Kappa statistic. We measured errors of inclusion and exclusion of the scorecard relative to the other methods. We also gathered perceptions of the scorecard criteria through qualitative interviews with stakeholders at multiple levels of the health system. The distribution of the scorecard was less skewed than other wealth measures and not truncated, but demonstrated clumping. There was a higher level of agreement between the scorecard and the wealth index than consumption expenditure. The scorecard identified a similar number of poor households as the "basic needs" poverty line based on monthly consumption expenditure, with only 45 % errors of inclusion. However, it failed to pick up half of those living below the "basic needs" poverty line as being poor. Stakeholders supported the inclusion of water sources, income, food security and disability measures but had reservations about other items on the scorecard. In choosing poverty identification strategies for programmes seeking to enhance health equity it's necessary to balance between community acceptability, local relevance and the need for such a strategy. It is important to ensure the strategy is efficient and less costly than alternatives in order to effectively reduce

  20. Interband cascade laser-based ppbv-level mid-infrared methane detection using two digital lock-in amplifier schemes

    Science.gov (United States)

    Song, Fang; Zheng, Chuantao; Yu, Di; Zhou, Yanwen; Yan, Wanhong; Ye, Weilin; Zhang, Yu; Wang, Yiding; Tittel, Frank K.

    2018-03-01

    A parts-per-billion in volume (ppbv) level mid-infrared methane (CH4) sensor system was demonstrated using second-harmonic wavelength modulation spectroscopy (2 f-WMS). A 3291 nm interband cascade laser (ICL) and a multi-pass gas cell (MPGC) with a 16 m optical path length were adopted in the reported sensor system. Two digital lock-in amplifier (DLIA) schemes, a digital signal processor (DSP)-based DLIA and a LabVIEW-based DLIA, were used for harmonic signal extraction. A limit of detection (LoD) of 13.07 ppbv with an averaging time of 2 s was achieved using the DSP-based DLIA and a LoD of 5.84 ppbv was obtained using the LabVIEW-based DLIA with the same averaging time. A rise time of 0→2 parts-per-million in volume (ppmv) and fall time of 2→0 ppmv were observed. Outdoor atmospheric CH4 concentration measurements were carried out to evaluate the sensor performance using the two DLIA schemes.

  1. Numerical simulations of natural or mixed convection in vertical channels: comparisons of level-set numerical schemes for the modeling of immiscible incompressible fluid flows

    International Nuclear Information System (INIS)

    Li, R.

    2012-01-01

    The aim of this research dissertation is at studying natural and mixed convections of fluid flows, and to develop and validate numerical schemes for interface tracking in order to treat incompressible and immiscible fluid flows, later. In a first step, an original numerical method, based on Finite Volume discretizations, is developed for modeling low Mach number flows with large temperature gaps. Three physical applications on air flowing through vertical heated parallel plates were investigated. We showed that the optimum spacing corresponding to the peak heat flux transferred from an array of isothermal parallel plates cooled by mixed convection is smaller than those for natural or forced convections when the pressure drop at the outlet keeps constant. We also proved that mixed convection flows resulting from an imposed flow rate may exhibit unexpected physical solutions; alternative model based on prescribed total pressure at inlet and fixed pressure at outlet sections gives more realistic results. For channels heated by heat flux on one wall only, surface radiation tends to suppress the onset of re-circulations at the outlet and to unify the walls temperature. In a second step, the mathematical model coupling the incompressible Navier-Stokes equations and the Level-Set method for interface tracking is derived. Improvements in fluid volume conservation by using high order discretization (ENO-WENO) schemes for the transport equation and variants of the signed distance equation are discussed. (author)

  2. Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants

    International Nuclear Information System (INIS)

    Kercel, S.W.; Moore, M.R.; Blakeman, E.D.; Ewing, P.D.; Wood, R.T.

    1996-11-01

    This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants

  3. Why consider subseabed disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    Heath, G.R.; Hollister, C.D.; Anderson, D.R.; Leinen, M.

    1980-01-01

    Large areas of the deep seabed warrant assessment as potential disposal sites for high-level radioactive waste because: (1) they are far from seismically and tectonically active lithospheric plate boundaries; (2) they are far from active or young volcanos; (3) they contain thick layers of very uniform fine-grained clays; (4) they are devoid of natural resources likely to be exploited in the forseeable future; (5) the geologic and oceanographic processes governing the deposition of sediments in such areas are well understood, and are remarkably insensitive to past oceanographic and climatic changes; and (6) sedmentary records of tens of millions of years of slow, uninterrupted deposition of fine grained clay support predictions of the future stability of such sites. Data accumulated to date on the permeability, ion-retardation properties, and mechanical strength of pelagic clay sediments indicate that they can act as a primary barrier to the escape of buried nuclides. Work in progress should determine within the current decade whether subseabed disposal is environmentally acceptable and technically feasible, as well as address the legal, political and social issues raised by this new concept

  4. Why consider subseabed disposal of high-level nuclear wastes

    International Nuclear Information System (INIS)

    Heath, G.R.; Hollister, C.D.; Anderson, D.R.; Leinen, M.

    1983-01-01

    There exist large areas of the deep seabed that warrant assessment as potential disposal sites for high-level radioactive wastes because (1) they are far from seismically and tectonically active lithospheric plate boundaries; (2) they are far from active or young volcanoes; (3) they contain thick layers of very uniform fine-grained clays; (4) they are devoid of natural resources likely to be exploited in the foreseeable future; (5) the geologic and oceanographic processes governing the deposition of sediments in such areas are well understood, and have been remarkably insensitive to past oceanic and climatic changes; and (6) sedimentary records of tens of millions of years of slow, uninterrupted deposition of fine-grained clay support predictions of the future stability of such sites. Data accumulated to date on the permeability, ion-retardation properties, and mechanical strength of pelagic clayey sediments indicate that they can act as a primary barrier to the escape of buried radionuclides. Work in progress should determine within the current decade whether subseabed disposal is environmentally acceptable and technically feasible, as well as address the legal, political, and social issues raised by this new concept

  5. A method for assay of special nuclear material in high level liquid waste streams

    International Nuclear Information System (INIS)

    Venkata Subramani, C.R.; Swaminathan, K.; Asuvathraman, R.; Kutty, K.V.G.

    2003-01-01

    The assay of special nuclear material in the high level liquid waste streams assumes importance as this is the first stage in the extraction cycle and considerable losses of plutonium could occur here. This stream contains all the fission products as also the minor actinides and hence normal nuclear techniques cannot be used without prior separation of the special nuclear material. This paper presents the preliminary results carried out using wavelength dispersive x-ray fluorescence as part of the developmental efforts to assay SNM in these streams by instrumental techniques. (author)

  6. Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

    International Nuclear Information System (INIS)

    Saphier, D.

    1978-09-01

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

  7. Determination of activation level energy of nuclear isomers by calibration of microspectra of radioactive sources

    International Nuclear Information System (INIS)

    Veres, A.; Pavlicsek, I.

    1980-01-01

    Nuclear isomers with unknown activation level were irradiated by calibrated radioactive sources. The integral cross sections were calculated for different energies of the sources. The activation energy was given by values coinciding with each other within the limits of error. The method made the determination of the unknown level of 1180+-10 keV of 195 Pt nucleus possible. (author)

  8. Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

    Science.gov (United States)

    Boatner, Lynn A.; Sales, Brian C.

    1989-01-01

    Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

  9. A Novel Scheme to Minimize Hop Count for GAF in Wireless Sensor Networks: Two-Level GAF

    Directory of Open Access Journals (Sweden)

    Vaibhav Soni

    2015-01-01

    Full Text Available In wireless sensor networks, geographic adaptive fidelity (GAF is one of the most popular energy-aware routing protocols. It conserves energy by identifying equivalence between sensors from a routing perspective and then turning off unnecessary sensors, while maintaining the connectivity of the network. Nevertheless, the traditional GAF still cannot reach the optimum energy usage since it needs more number of hops to transmit data packets to the sink. As a result, it also leads to higher packet delay. In this paper, we propose a modified version of GAF to minimize hop count for data routing, called two-level GAF (T-GAF. Furthermore, we use a generalized version of GAF called Diagonal-GAF (DGAF where two diagonal adjacent grids can also directly communicate. It has an advantage of less overhead of coordinator election based on the residual energy of sensors. Analysis and simulation results show significant improvements of the proposed work comparing to traditional GAF in the aspect of total hop count, energy consumption, total distance covered by the data packet before reaching the sink, and packet delay. As a result, compared to traditional GAF, it needs 40% to 47% less hop count and consumes 27% to 35% less energy to extend the network lifetime.

  10. Impact and Suggestion of Column-to-Surface Vertical Correction Scheme on the Relationship between Satellite AOD and Ground-Level PM2.5 in China

    Directory of Open Access Journals (Sweden)

    Wei Gong

    2017-10-01

    Full Text Available As China is suffering from severe fine particle pollution from dense industrialization and urbanization, satellite-derived aerosol optical depth (AOD has been widely used for estimating particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5. However, the correlation between satellite AOD and ground-level PM2.5 could be influenced by aerosol vertical distribution, as satellite AOD represents the entire column, rather than just ground-level concentration. Here, a new column-to-surface vertical correction scheme is proposed to improve separation of the near-surface and elevated aerosol layers, based on the ratio of the integrated extinction coefficient within 200–500 m above ground level (AGL, using the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP aerosol profile products. There are distinct differences in climate, meteorology, terrain, and aerosol transmission throughout China, so comparisons between vertical correction via CALIOP ratio and planetary boundary layer height (PBLH were conducted in different regions from 2014 to 2015, combined with the original Pearson coefficient between satellite AOD and ground-level PM2.5 for reference. Furthermore, the best vertical correction scheme was suggested for different regions to achieve optimal correlation with PM2.5, based on the analysis and discussion of regional and seasonal characteristics of aerosol vertical distribution. According to our results and discussions, vertical correction via PBLH is recommended in northwestern China, where the PBLH varies dramatically, stretching or compressing the surface aerosol layer; vertical correction via the CALIOP ratio is recommended in northeastern China, southwestern China, Central China (excluding summer, North China Plain (excluding Beijing, and the spring in the southeast coast, areas that are susceptible to exogenous aerosols and exhibit the elevated aerosol layer; and original AOD without vertical correction is

  11. Operational Assessment of ICDS Scheme at Grass Root Level in a Rural Area of Eastern India: Time to Introspect

    Science.gov (United States)

    Sahoo, Jyotiranjan; Mahajan, Preetam B; Bhatia, Vikas; Patra, Abhinash K; Hembram, Dilip Kumar

    2016-01-01

    Introduction Integrated Child Development Service (ICDS), a flagship program of Government of India (GoI) for early childhood development hasn’t delivered the desired results since its inception four decades ago. This could be due to infrastructural problems, lack of awareness and proper utilization by the local people, inadequate program monitoring and corruption in food supplies, etc. This study is an audit of 36 Anganwadi centres at Khordha district, Odisha, to evaluate the implementation of the ICDS. Aim To assess operational aspects of ICDS program in a rural area of Odisha, in Eastern India. Materials and Methods A total of 36 out of 50 Anganwadi Centres (AWCs) were included in the study. We interviewed the Anganwadi Workers (AWW) and carried out observations on the AWCs using a checklist. We gathered information under three domains manpower resource, material resource and functional aspects of the AWC. Results Most of the AWCs were adequately staffed. Most of the AWWs were well educated. However, more than 85% of the AWCs did not have designated building for daily functioning which resulted in issues related to implementation of program. Water, toilet and electricity facilities were almost non-existent. Indoor air pollution posed a serious threat to the health of the children. Lack of play materials; lack of health assessment tools for promoting, monitoring physical and mental development; and multiple de-motivating factors within the work environment, eventually translated into lack of faith among the beneficiaries in the rural community. Conclusion Inadequate infrastructure and logistic supply were the most prominent issues found, which resulted in poor implementation of ICDS program. Strengthening of grass root level facilities based on need assessment, effective monitoring and supervision will definitely help in revamping the ICDS program in rural areas. PMID:28208890

  12. The scope and nature of the problem of high level nuclear waste disposal

    International Nuclear Information System (INIS)

    Jennekens, J.

    1981-09-01

    The disposal of high level nuclear waste poses a challenge to the Canadian technical and scientific communities, but a much greater challenge to government and industry leaders who must convince the public that the so-called 'problem' can be resolved by a pragmatic approach utilizing existing skills and knowledge. This paper outlines the objectives of radioactive waste management, the quantities of high level waste expected to be produced by the Canadian nuclear power program, the regulatory process which will apply and the government initiatives which have been and will be taken to ensure that the health, safety, security, and environmental interests of the public will be protected. (author)

  13. Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

    International Nuclear Information System (INIS)

    Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B.

    2017-01-01

    The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, 3 H, 14 C, 55 Fe, 59 Ni, 63 Ni, 90 Sr, 93 Zr, 94 Nb, 99 Tc, 129 I, 235 U, 238 U, 238 Pu, 239 + 240 Pu, 241 Pu, 242 Pu, 241 Am, 242 Cm e 243 + 244 Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

  14. Communication dated 30 May 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA concerning enrichment bonds - A voluntary scheme for reliable access to nuclear fuel

    International Nuclear Information System (INIS)

    2007-01-01

    The Secretariat has received a letter dated 30 May 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA attaching a UK Non-paper entitled 'Food for Thought: Enrichment Bonds - A Voluntary Scheme for Reliable Access to Nuclear Fuel'. As requested in that letter, the letter and the attachment is now being circulated for the information of all Member States

  15. On the evaluation of semiclassical nuclear many-particle many-hole level densities

    International Nuclear Information System (INIS)

    Blin, A.H.; Hiller, B.; Schuck, P.; Yannouleas, C.

    1985-10-01

    An exact general scheme is described to calculate the m-particle n-hole fermion level densities for an arbitrary single particle Hamiltonian taking into account the Pauli exclusion principle. This technique is applied to obtain level densities of the three dimensional isotropic harmonic oscillator semiclassically in the Thomas-Fermi approach. In addition, we study the l-particle l-hole level density of the Woods-Saxon potential. For the harmonic oscillator we analyze the temperature dependence of the linear response function and the influence of pairing correlations on the l-particle l-hole level density. Finally, a Taylor expansion method of the m-particle n-hole level densities is discussed

  16. Analysis of opinion about nuclear energy and sustainability in a graduate level population

    International Nuclear Information System (INIS)

    Meza L, C.D.; Arredondo S, C.

    2007-01-01

    The Mexican society has a modest knowledge of the nuclear energy, even at the participant students of superior education level in this survey is finds a scarce compression with regard to their obtaining, use and manage. As a result of the lack of interest of the same society and at the problems that know each other like they are: the pollutants that it produces those nuclear waste and the possible use or warlike end, a fear is believed about this energy type. In the Superior School of Physics and Mathematics there is the possibility to make studies so much at master degree level in the one fear of the nuclear energy and the applications of the same one in peaceful uses. However, particularly the studies at master level seem to be immersed in a crisis that requires of different supports to be resolved. For all it previous was thought in carrying out a survey inside a student population with superior level to know the opinion and the knowledge on the nuclear energy in Mexico. In this work the results of the survey are analyzed with the purpose of to determine which is the knowledge of the community mentioned regarding the other energy types, the impact that they have these in the environment, the sustenance of the same ones and in particular on knowledge about the nuclear energy considering the aspects before mentioned. With base had said analysis settles down that the interviewed community knows very little about the nuclear energy but they show interest to study and to obtain bigger information about the same one, for what is very important to diffuse but and better information on the nuclear energy to the population's strata, because it is of supposing that the rest of the population has erroneous information on the nuclear energy. In particular for the community of the Superior School of Physics and Mathematics the diffusion of all the benefits of the peaceful applications of the nuclear energy, including the capacity to generate enormous quantities and energy

  17. Training at the masters degree level in physics and technology of nuclear reactors in the uk

    International Nuclear Information System (INIS)

    Weaver, D.R.

    2000-01-01

    This paper discusses the current situation of university-based training for the nuclear power industry in the UK, drawing on information gathered as part of the survey for a review currently being undertaken by the Committee for Technical and Economic Studies on Nuclear Energy Development and Fuel Cycle (NDC) of the Nuclear Energy Agency (NEA) of the OECD. A particular focus will be the Physics and Technology of Nuclear Reactors MSc course at the University of Birmingham. In the past there were other similar MSc courses in the UK, but through the evolution of time the Birmingham course is now unique in its role of providing masters level training so specifically aimed at the commercial nuclear programme. Mention will, however, be made of other training at the postgraduate level elsewhere in the UK. A description is given of the need to consider a new form of relationship between industry and university in order to provide optimise the provision of masters level training. (author)

  18. The nuclear physical method for high pressure steam manifold water level gauging and its error

    International Nuclear Information System (INIS)

    Li Nianzu; Li Beicheng; Jia Shengming

    1993-10-01

    A new method, which is non-contact on measured water level, for measuring high pressure steam manifold water level with nuclear detection technique is introduced. This method overcomes the inherent drawback of previous water level gauges based on other principles. This method can realize full range real time monitoring on the continuous water level of high pressure steam manifold from the start to full load of boiler, and the actual value of water level can be obtained. The measuring errors were analysed on site. Errors from practical operation in Tianjin Junliangcheng Power Plant and in laboratory are also presented

  19. Atmospheric Dispersion Simulation for Level 3 PSA at Ulchin Nuclear Site using a PUFF model

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Jun; Han, Seok-Jung; Jeong, Hyojoon; Jang, Seung-Cheol [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    Air dispersion prediction is a key in the level 3 PSA to predict radiation releases into the environment for preparing an effective strategy for an evacuation as a basis of the emergency preparedness. To predict the atmospheric dispersion accurately, the specific conditions of the radiation release location should be considered. There are various level 3 PSA tools and MACSS2 is one of the widely used level 3 PSA tools in many countries including Korea. Due to the characteristics of environmental conditions in Korea, it should be demonstrated that environmental conditions of Korea nuclear sites can be appropriately illustrated by the tool. In Korea, because all nuclear power plants are located on coasts, sea and land breezes might be a significant factor. The objectives of this work is to simulate the atmospheric dispersion for Ulchin nuclear site in Korea using a PUFF model and to generate the data which can be used for the comparison with that of PLUME model. A nuclear site has own atmospheric dispersion characteristics. Especially in Korea, nuclear sites are located at coasts and it is expected that see and land breeze effects are relatively high. In this work, the atmospheric dispersion at Ulchin nuclear site was simulated to evaluate the effect of see and land breezes in four seasons. In the simulation results, it was observed that the wind direction change with time has a large effect on atmospheric dispersion. If the result of a PLUME model is more conservative than most severe case of a PUFF model, then the PLUME model could be used for Korea nuclear sites in terms of safety assessment.

  20. French diagnostic reference levels in diagnostic radiology, computed tomography and nuclear medicine: 2004-2008 Review

    International Nuclear Information System (INIS)

    Roch, P.; Aubert, B.

    2013-01-01

    After 5 y of collecting data on diagnostic reference levels (DRLs), the Nuclear Safety and Radiation Protection French Inst. (IRSN) presents the analyses of this data. The analyses of the collected data for radiology, computed tomography (CT) and nuclear medicine allow IRSN to estimate the level of regulatory application by health professionals and the representativeness of current DRL in terms of relevant examinations, dosimetric quantities, numerical values and patient morphologies. Since 2004, the involvement of professionals has highly increased, especially in nuclear medicine, followed by CT and then by radiology. Analyses show some discordance between regulatory examinations and clinical practice. Some of the dosimetric quantities used for the DRL setting are insufficient or not relevant enough, and some numerical values should also be reviewed. On the basis of these findings, IRSN formulates recommendations to update regulatory DRL with current and relevant examination lists, dosimetric quantities and numerical values. (authors)

  1. Lead-iron phosphate glass: a stable storage medium for high-level nuclear waste

    International Nuclear Information System (INIS)

    Sales, B.C.; Boatner, L.A.

    1984-01-01

    Results are presented which show that lead-iron phosphate glasses are a promising new waste form for the safe immobilization of both high-level defense and high-level commercial radioactive waste. Relative to the borosilicate nuclear waste glasses that are currently the ''reference'' waste form for the long-term disposal of nuclear waste, lead-iron phosphate glasses have several distinct advantages: (1) an aqueous corrosion rate that is about 1000 times lower, (2) a processing temperature that is 100 0 to 250 0 C lower and, (3) a much lower melt viscosity in the temperature range from 800 0 to 1000 0 C. Most significantly, the lead-iron phosphate waste form can be processed using a technology similar to that developed for borosilicate nuclear waste glasses

  2. Alternative health insurance schemes

    DEFF Research Database (Denmark)

    Keiding, Hans; Hansen, Bodil O.

    2002-01-01

    In this paper, we present a simple model of health insurance with asymmetric information, where we compare two alternative ways of organizing the insurance market. Either as a competitive insurance market, where some risks remain uninsured, or as a compulsory scheme, where however, the level...... competitive insurance; this situation turns out to be at least as good as either of the alternatives...

  3. Bridging nuclear safety, security and safeguards at geological disposl of high level radioactive waste and spent nuclear fuel

    International Nuclear Information System (INIS)

    Niemeyer, Irmgard; Deissmann, Guido; Bosbach, Dirk

    2016-01-01

    Findings and recommendations: • Further R&D needed to identify concepts, methods and technologies that would be best suited for the holistic consideration of safety, security and safeguards provisions of geological disposal. • 3S ‘toolbox’, including concepts, methods and technologies for: ■ material accountancy, ■ measurement techniques for spent fuel verification, ■ containment and surveillance, ■ analysis of open source information, ■ environmental sampling and monitoring, ■ continuity of knowledge, ■ design implications. •: Bridging safety, security and safeguards in research funding and research activities related to geological disposal of high-level radioactive waste and spent nuclear fuel.

  4. Levelized Costs for Nuclear, Gas and Coal for Electricity, under the Mexican Scenario

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, J.C.; Alonso, G.; Ramirez, R.; Gomez, A.; Ortiz, J.; Longoria, L.C.

    2004-10-06

    In the case of new nuclear power stations, it is necessary to pay special attention to the financial strategy that will be applied, time of construction, investment cost, and the discount and return rate. The levelized cost quantifies the unitary cost of the electricity (the kWh) generated during the lifetime of the nuclear power plant; and allows the immediate comparison with the cost of other alternative technologies. The present paper shows levelized cost for different nuclear technologies and it provides comparison among them as well as with gas and coal electricity plants. For the calculations we applied our own methodology to evaluate the levelized cost considering investment, fuel and operation and maintenance costs, making assumptions for the Mexican market, and taking into account the gas prices projections. The study also shows comparisons using different discount rates (5% and 10%), and some comparisons between our results and an OECD 1998 study. The results are i n good agreement and shows that nuclear option is cost competitive in Mexico on the basis of levelized costs.

  5. Numerical investigation of high level nuclear waste disposal in deep anisotropic geologic repositories

    KAUST Repository

    Salama, Amgad; El Amin, Mohamed F.; Sun, Shuyu

    2015-01-01

    One of the techniques that have been proposed to dispose high level nuclear waste (HLW) has been to bury them in deep geologic formations, which offer relatively enough space to accommodate the large volume of HLW accumulated over the years since

  6. Requirements for a top level hierarchy for a next generation nuclear data format

    International Nuclear Information System (INIS)

    Brown, D.A.; Koning, A.; Roubtsov, Y.D.; Mills, R.; Mattoon, C.M.; Beck, B.; Vogt, R.

    2014-01-01

    This document attempts to compile the requirements for the top-levels of a hierarchical arrangement of nuclear data such as is found in the ENDF format. This set of requirements will be used to guide the development of a new set of formats to replace the legacy ENDF format. (authors)

  7. Chem I Supplement. Chemistry Related to Isolation of High-Level Nuclear Waste.

    Science.gov (United States)

    Hoffman, Darleane C.; Choppin, Gregory R.

    1986-01-01

    Discusses some of the problems associated with the safe disposal of high-level nuclear wastes. Describes several waste disposal plans developed by various nations. Outlines the multiple-barrier concept of isolation in deep geological questions associated with the implementation of such a method. (TW)

  8. Effects of pairing correlation on nuclear level density parameter and nucleon separation energy

    International Nuclear Information System (INIS)

    Rajesekaran, T.R.; Selvaraj, S.

    2002-01-01

    A systematic study of effects of pairing correlations on nuclear level density parameter 'a' and neutron separation energy S N is presented for 152 Gd using statistical theory of nuclei with deformation, collective and noncollective rotational degrees of freedom, shell effects, and pairing correlations

  9. Levelized Costs for Nuclear, Gas and Coal for Electricity, under the Mexican Scenario

    International Nuclear Information System (INIS)

    Palacios, J.C.; Alonso, G.; Ramirez, R.; Gomez, A.; Ortiz, J.; Longoria, L.C.

    2004-01-01

    In the case of new nuclear power stations, it is necessary to pay special attention to the financial strategy that will be applied, time of construction, investment cost, and the discount and return rate. The levelized cost quantifies the unitary cost of the electricity (the kWh) generated during the lifetime of the nuclear power plant; and allows the immediate comparison with the cost of other alternative technologies. The present paper shows levelized cost for different nuclear technologies and it provides comparison among them as well as with gas and coal electricity plants. For the calculations we applied our own methodology to evaluate the levelized cost considering investment, fuel and operation and maintenance costs, making assumptions for the Mexican market, and taking into account the gas prices projections. The study also shows comparisons using different discount rates (5% and 10%), and some comparisons between our results and an OECD 1998 study. The results are i n good agreement and shows that nuclear option is cost competitive in Mexico on the basis of levelized costs

  10. Line-of-Credit Payment Scheme and Its Impact on the Retailer’s Ordering Policy with Inventory-Level-Dependent Demand

    Directory of Open Access Journals (Sweden)

    Tao Jia

    2016-01-01

    Full Text Available Practically, the supplier frequently offers the retailer credit period to stimulate his/her ordering quantity. However, such credit-period-only policy may lead to the dilemma that the supplier’s account receivable increases with sale volume during delay period, especially for the item with inventory-level-dependent demand. Thus, a line-of-credit (LOC payment scheme is usually adopted by the supplier for better controlling account receivables. In this paper, the two-parameter LOC clause is firstly applied to develop an economic order quantity (EOQ model with inventory-level-dependent demand, aiming to explore its influences on the retailer’s ordering policy. Under this new policy, the retailer will be granted full delay payment if his/her order quantity is below a predetermined quantity. Otherwise, the retailer should make immediate payment for the excess part. After analyzing the relationships among parameters, two distinct cases and several theoretical results can be derived. From numerical examples, two incentives, a longer credit period and a lower rate of the retailer’s capital opportunity cost, should account for the retailer’s excessive ordering policy. And a well-designed LOC clause can be applied to induce the retailer to place an appropriate ordering quantity and ensure the supplier maintains a reasonable account receivable.

  11. German Spent Nuclear Fuel Legacy: Characteristics and High-Level Waste Management Issues

    Directory of Open Access Journals (Sweden)

    A. Schwenk-Ferrero

    2013-01-01

    Full Text Available Germany is phasing-out the utilization of nuclear energy until 2022. Currently, nine light water reactors of originally nineteen are still connected to the grid. All power plants generate high-level nuclear waste like spent uranium or mixed uranium-plutonium dioxide fuel which has to be properly managed. Moreover, vitrified high-level waste containing minor actinides, fission products, and traces of plutonium reprocessing loses produced by reprocessing facilities has to be disposed of. In the paper, the assessments of German spent fuel legacy (heavy metal content and the nuclide composition of this inventory have been done. The methodology used applies advanced nuclear fuel cycle simulation techniques in order to reproduce the operation of the German nuclear power plants from 1969 till 2022. NFCSim code developed by LANL was adopted for this purpose. It was estimated that ~10,300 tonnes of unreprocessed nuclear spent fuel will be generated until the shut-down of the ultimate German reactor. This inventory will contain ~131 tonnes of plutonium, ~21 tonnes of minor actinides, and 440 tonnes of fission products. Apart from this, ca.215 tonnes of vitrified HLW will be present. As fission products and transuranium elements remain radioactive from 104 to 106 years, the characteristics of spent fuel legacy over this period are estimated, and their impacts on decay storage and final repository are discussed.

  12. Lead-iron phosphate glass as a containment medium for the disposal of high-level nuclear wastes

    Science.gov (United States)

    Boatner, L.A.; Sales, B.C.

    1984-04-11

    Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

  13. Structural Equation Modelling with Three Schemes Estimation of Score Factors on Partial Least Square (Case Study: The Quality Of Education Level SMA/MA in Sumenep Regency)

    Science.gov (United States)

    Anekawati, Anik; Widjanarko Otok, Bambang; Purhadi; Sutikno

    2017-06-01

    Research in education often involves a latent variable. Statistical analysis technique that has the ability to analyze the pattern of relationship among latent variables as well as between latent variables and their indicators is Structural Equation Modeling (SEM). SEM partial least square (PLS) was developed as an alternative if these conditions are met: the theory that underlying the design of the model is weak, does not assume a certain scale measurement, the sample size should not be large and the data does not have the multivariate normal distribution. The purpose of this paper is to compare the results of modeling of the educational quality in high school level (SMA/MA) in Sumenep Regency with structural equation modeling approach partial least square with three schemes estimation of score factors. This paper is a result of explanatory research using secondary data from Sumenep Education Department and Badan Pusat Statistik (BPS) Sumenep which was data of Sumenep in the Figures and the District of Sumenep in the Figures for the year 2015. The unit of observation in this study were districts in Sumenep that consists of 18 districts on the mainland and 9 districts in the islands. There were two endogenous variables and one exogenous variable. Endogenous variables are the quality of education level of SMA/MA (Y1) and school infrastructure (Y2), whereas exogenous variable is socio-economic condition (X1). In this study, There is one improved model which represented by model from path scheme because this model is a consistent, all of its indicators are valid and its the value of R-square increased which is: Y1=0.651Y2. In this model, the quality of education influenced only by the school infrastructure (0.651). The socio-economic condition did not affect neither the school infrastructure nor the quality of education. If the school infrastructure increased 1 point, then the quality of education increased 0.651 point. The quality of education had an R2 of 0

  14. Mineral-modeled ceramics for long-term storage of high-level nuclear wastes

    International Nuclear Information System (INIS)

    Vance, E.R.

    1980-01-01

    Over the past ten years, Penn State's Materials Research Laboratory has done extensive work on mineral-modeled ceramics for high-level nuclear waste storage. These ceramics are composed of several mineral analogues that form a monolithic polycrystalline aggregate. Mineral-modeling can be made in a similar fashion to nuclear waste glasses, and their naturally occurring analogues are known to last millions, and even billions, of years in hot, wet conditions. It is believed that such ceramics could reduce dispersal of radionuclides by leaching to a minimum

  15. What are Spent Nuclear Fuel and High-Level Radioactive Waste?

    International Nuclear Information System (INIS)

    2002-01-01

    Spent nuclear fuel and high-level radioactive waste are materials from nuclear power plants and government defense programs. These materials contain highly radioactive elements, such as cesium, strontium, technetium, and neptunium. Some of these elements will remain radioactive for a few years, while others will be radioactive for millions of years. Exposure to such radioactive materials can cause human health problems. Scientists worldwide agree that the safest way to manage these materials is to dispose of them deep underground in what is called a geologic repository

  16. The Hagedorn spectrum, nuclear level densities and first order phase transitions

    International Nuclear Information System (INIS)

    Moretto, Luciano G.; Larsen, A. C.; Guttormsen, M.; Siem, S.

    2015-01-01

    An exponential mass spectrum, like the Hagedorn spectrum, with slope 1/T H was interpreted as fixing an upper limiting temperature T H that the system can achieve. However, thermodynamically, such spectrum indicates a 1 st order phase transition at a fixed temperature T H . A much lower energy example is the log linear level nuclear density below the neutron binding energy that prevails throughout the nuclear chart. We show that, for non-magic nuclei, such linearity implies a 1 st order phase transition from the pairing superfluid to an ideal gas of quasi particles

  17. The Hagedorn spectrum, nuclear level densities and first order phase transitions

    Energy Technology Data Exchange (ETDEWEB)

    Moretto, Luciano G., E-mail: lgmoretto@lbl.gov [Department of Chemistry, University of California, Berkeley, Lawrence Berkeley National Laboratory 1 Cyclotron Road, Berkeley, CA 94720 (United States); Larsen, A. C.; Guttormsen, M.; Siem, S. [Department of Physics, University of Oslo, N-0316 Oslo (Norway)

    2015-10-15

    An exponential mass spectrum, like the Hagedorn spectrum, with slope 1/T{sub H} was interpreted as fixing an upper limiting temperature T{sub H} that the system can achieve. However, thermodynamically, such spectrum indicates a 1{sup st} order phase transition at a fixed temperature T{sub H}. A much lower energy example is the log linear level nuclear density below the neutron binding energy that prevails throughout the nuclear chart. We show that, for non-magic nuclei, such linearity implies a 1{sup st} order phase transition from the pairing superfluid to an ideal gas of quasi particles.

  18. Differentiated influences of benefit and risk perceptions on nuclear power acceptance according to acceptance levels. Evidence from Korea

    International Nuclear Information System (INIS)

    Roh, Seungkook; Lee Jinwon

    2017-01-01

    The perceived benefit and risk of nuclear power generation have received considerable attention as determinants of the public's nuclear power acceptance. However, the contingency of the relative importance of these benefit and risk has been less explored. Using Korea as an example, this study explores the possibility that the relative importance of perceived benefit and risk on nuclear power acceptance depends on acceptance levels. Our results from latent class analysis and multinomial probit show that, in determining whether an individual shows a moderate level of nuclear power acceptance rather than a low level, perceived risk plays a dominant role compared to perceived benefit; however, regarding whether he/she shows a high level of nuclear power acceptance rather than a moderate level, this relative importance is reversed. These results carry practical implications for risk governance of nuclear power, particularly with regard to communication with the public. (author)

  19. Change in the financing scheme for radioactive waste in Germany

    International Nuclear Information System (INIS)

    Svobodová, Tereza

    2018-01-01

    Financing radioactive waste management is an issue every country using nuclear power has to deal with. A European directive even makes this binding for Euratom Member States. Germany changed its financing scheme entirely during the past year, thereby moving closer to other states' schemes. Germany replaced the funds put aside by the operators with a public fund to which the companies contribute. Now it is the government that is responsible for radioactive waste. This paper describes the regulation and information collection system on the European level and analyses the former and current German systems, their advantages and potential hazards. (orig.)

  20. Voluntary agreements, implementation and efficiency. European relevance of case study results. Reflections on transferability to voluntary agreement schemes at the European level

    Energy Technology Data Exchange (ETDEWEB)

    Helby, Peter

    2000-04-01

    As a policy instrument, voluntary agreements often fascinate policy-makers.This is fuelled by a number of assumed advantages, such as the opportunity for co-operation rather than confrontation, speed and flexibility and the cost-effectiveness. Some advantages might even be accentuated at the European level: Co-operation has added advantage at the European level where the culture of consensus decision is strong. Flexibility is extra attractive for policy makers dealing with an economy less homogeneous than the average national economy. Speed is certainly welcomed by policy-makers otherwise faced with the slow-winding European legislative process. Cost-effectiveness is eagerly sought by European policy makers facing tight administrative budgets and staff limits. This report examines lessons from the VAIE case studies that may be useful to policy makers engaged in the development of voluntary approaches at the European level. These case studies are about voluntary agreement schemes for industrial energy efficiency deployed in Denmark, France, Germany, Netherlands, and Sweden. For a summary of these case studies, please refer to the the VAIE final report. More detailed information is available in the VAIE national reports. It needs to be emphasised that the empirical base is very narrow. The 'lessons' presented can only be hypotheses, based on an inductive leap from a very narrow experience. The reader will need to check these hypotheses against her own broader experience and personal judgement. According to the principle of subsidiarity, voluntary agreements should be implemented at the European level only if that would have significant advantage over national action. Action at the European level, rather than the national level, would have these potential advantages: Being more consistent with the development of the single market; Allowing higher demands on energy efficiency without negative effect on competitiveness and employment; Stimulating company

  1. Status of the high-level nuclear waste disposal program in Japan

    International Nuclear Information System (INIS)

    Uematsu, K.

    1985-01-01

    The Japan Atomic Energy Commission (JAEC) initiated a high-level radioactive waste disposal program in 1976. Since then, the Advisory Committee on Radioactive Waste Management of JAEC has revised the program twice. The latest revision was issued in 1984. The committee recommended a four-phase program and the last phase calls for the beginning of emplacement of the high-level nuclear waste into a selected repository in the Year 2000. The first phase is already completed, and the second phase of this decade calls for the selection of a candidate disposal site and the conducting of the RandD of waste disposal in an underground research laboratory and in a hot test facility. This paper covers the current status of the high-level nuclear waste disposal program in Japan

  2. Advanced I and C system of security level for nuclear power station

    International Nuclear Information System (INIS)

    Liu Yanyang

    2001-01-01

    Advanced I and C system of security level using for PWR developed by Framatome and Schneider collective, SPINLINE3, are introduced. The technology is used to outside reactor nuclear measurement system in Qinshan II period. It's succeed benefits by Framatome and Schneider's more years development experience in nuclear power station digitallization security level I and C system field, which improve security and reliability of PWR, and, easy operation and maintains. SPINLINE3 based on digitallization and modularization technical proposal, and covered entireness reactor protect system and correlative control system. The paper also introduce CLARISSE (computer aided design aid) and SCADE (embedded software aid) for developing SPINLINE3. SPINLINE3 fills correlative IS and rule, based on software and hardware unit which certificate and launch into operation. After brief review of Framatome and Schneider's experience, the paper are introducing design guideline, application technology and how to fill demand of security level I and C system

  3. Spin assignments of nuclear levels above the neutron binding energy in $^{88}$Sr

    CERN Multimedia

    Neutron resonances reveal nuclear levels in the highly excited region of the nucleus around the neutron binding energy. Nuclear level density models are therefore usually calibrated to the number of observed levels in neutron-induced reactions. The gamma-ray cascade from the decay of the highly excited compound nucleus state to the ground state show dierences dependent on the initial spin. This results in a dierence in the multiplicity distribution which can be exploited. We propose to use the 4${\\pi}$ total absorption calorimeter (TAC) at the n TOF facility to determine the spins of resonances formed by neutrons incident on a metallic $^{87}$Sr sample by measuring the gamma multiplicity distributions for the resolved resonances. In addition we would like to use the available enriched $^{87}$Sr target for cross section measurements with the C$\\scriptscriptstyle{6}$D$\\scriptscriptstyle{6}$ detector setup.

  4. US program for the immobilization of high-level nuclear wastes

    International Nuclear Information System (INIS)

    Crandall, J.L.

    1979-01-01

    A program has been developed for long-term management of high-level nuclear waste. The Savannah River Operations Office of the US Department of Energy is acting as the lead office for this program with technical advice from the E.I. du Pont de Nemours and Company. The purpose of the long-term program is to immobilize the DOE high-level waste in forms that act as highly efficient barriers against radionuclide release to the disposal site and to provide technology for similar treatment of commercial high-level waste in case reprocessing of commercial nuclear fuels is ever resumed. Descriptions of existing DOE and commercial wastes, program strategy, program expenditures, development of waste forms, evaluation and selection of waste forms, regulatory aspects of waste form selection, project schedules, and cost estimates for immobilization facilities are discussed

  5. Development of anodic stripping voltametry for the determination of palladium in high level nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, T. K. [North Carolina State University, Raleigh (United States); Sharma, H. S.; Affarwal, S. K. [Bhabha Atomic Research Centre, Mumbai (India); Jain, P. C. [Meerut College, Meerut (India)

    2012-12-15

    Deposition potential, deposition time, square wave frequency, rotation speed of the rotating disc electrode, and palladium concentration were studied on a Glassy Carbon Electrode (GCE) in 0.01M HCl for the determination of palladium in High Level Nuclear Waste (HLNW) by anodic stripping voltammetry. Experimental conditions were optimized for the determination of palladium at two different, 10-8 and 10-7 M, levels. Error and standard deviation of this method were under 1% for all palladium standard solutions. The developed technique was successfully applied as a subsidiary method for the determination of palladium in simulated high level nuclear waste with very good precision and high accuracy (under 1 % error and standard deviation).

  6. An instrumentation and control philosophy for high-level nuclear waste processing facilities

    International Nuclear Information System (INIS)

    Weigle, D.H.

    1990-01-01

    The purpose of this paper is to present an instrumentation and control philosophy which may be applied to high-level nuclear waste processing facilities. This philosophy describes the recommended criteria for automatic/manual control, remote/local control, remote/local display, diagnostic instrumentation, interlocks, alarm levels, and redundancy. Due to the hazardous nature of the process constituents of a high-level nuclear waste processing facility, it is imperative that safety and control features required for accident-free operation and maintenance be incorporated. A well-instrumented and controlled process, while initially more expensive in capital and design costs, is generally safer and less expensive to operate. When the long term cost savings of a well designed process is coupled with the high savings enjoyed by accident avoidance, the benefits far outweigh the initial capital and design costs

  7. Development of fuzzy algorithm with learning function for nuclear steam generator level control

    International Nuclear Information System (INIS)

    Park, Gee Yong; Seong, Poong Hyun

    1993-01-01

    A fuzzy algorithm with learning function is applied to the steam generator level control of nuclear power plant. This algorithm can make its rule base and membership functions suited for steam generator level control by use of the data obtained from the control actions of a skilled operator or of other controllers (i.e., PID controller). The rule base of fuzzy controller with learning function is divided into two parts. One part of the rule base is provided to level control of steam generator at low power level (0 % - 30 % of full power) and the other to level control at high power level (30 % - 100 % of full power). Response time of steam generator level control at low power range with this rule base is shown to be shorter than that of fuzzy controller with direct inference. (Author)

  8. Mathematical modelling of heat production in deep geological repository of high-level nuclear waste

    International Nuclear Information System (INIS)

    Kovanda, O.

    2017-01-01

    Waste produced by nuclear industry requires special handling. Currently, there is a research taking place, focused at possibilities of nuclear waste storage in deep geological repositories, hosted in stable geological environment. The high-level nuclear waste produces significant amount of heat for a long time, which can affect either environment outside of or within the repository in a negative way. Therefore to reduce risks, it is desirable to know the principles of such heat production, which can be achieved using mathematical modeling. This thesis comes up with a general model of heat production-time dependency, dependable on initial composition of the waste. To be able to model real situations, output of this thesis needs to be utilized in an IT solution. (authors)

  9. Can Sisyphus succeed? Getting U.S. high-level nuclear waste into a geological repository.

    Science.gov (United States)

    North, D Warner

    2013-01-01

    The U.S. government has the obligation of managing the high-level radioactive waste from its defense activities and also, under existing law, from civilian nuclear power generation. This obligation is not being met. The January 2012 Final Report from the Blue Ribbon Commission on America's Nuclear Future provides commendable guidance but little that is new. The author, who served on the federal Nuclear Waste Technical Review Board from 1989 to 1994 and subsequently on the Board on Radioactive Waste Management of the National Research Council from 1994 to 1999, provides a perspective both on the Commission's recommendations and a potential path toward progress in meeting the federal obligation. By analogy to Sisyphus of Greek mythology, our nation needs to find a way to roll the rock to the top of the hill and have it stay there, rather than continuing to roll back down again. © 2012 Society for Risk Analysis.

  10. On-site storage of high level nuclear waste: attitudes and perceptions of local residents.

    Science.gov (United States)

    Bassett, G W; Jenkins-Smith, H C; Silva, C

    1996-06-01

    No public policy issue has been as difficult as high-level nuclear waste. Debates continue regarding Yucca Mountain as a disposal site, and-more generally-the appropriateness of geologic disposal and the need to act quickly. Previous research has focused on possible social, political, and economic consequences of a facility in Nevada. Impacts have been predicted to be potentially large and to emanate mainly from stigmatization of the region due to increased perceptions of risk. Analogous impacts from leaving waste at power plants have been either ignored or assumed to be negligible. This paper presents survey results on attitudes of residents in three counties where nuclear waste is currently stored. Topics include perceived risk, knowledge of nuclear waste and radiation, and impacts on jobs, tourism, and housing values from leaving waste on site. Results are similar to what has been reported for Nevada; the public is concerned about possible adverse effects from on-site storage of waste.

  11. Status of the United States' high-level nuclear waste disposal program

    International Nuclear Information System (INIS)

    Rusche, B.

    1985-01-01

    The Nuclear Waste Policy Act of 1982 is a remarkable piece of legislation in that there is general agreement on its key provisions. Nevertheless, this is a program intended to span more than a century, with some choices by Congress, states, Indian tribes and the nuclear power industry yet to be made. The crafters of the Act clearly recognized this. And further, the crafters recognized ''. . .that. . .state, Indian tribe and public participation in the planning and development of repositories is essential in order to promote public confidence in the safety of disposal of such waste and spent fuel . . . High-level radioactive waste and spent nuclear fuel have become major subjects of public concern, and appropriate precautions must be taken to ensure that such waste and spent fuel do not adversely affect the public health and safety and the environment for this or future generations

  12. Using electrochemical separation to reduce the volume of high-level nuclear waste

    International Nuclear Information System (INIS)

    Slater, S.A.; Gay, E.C.

    1998-01-01

    Argonne National Laboratory (ANL) has developed an electrochemical separation technique called electrorefining that will treat a variety of metallic spent nuclear fuel and reduce the volume of high-level nuclear waste that requires disposal. As part of that effort, ANL has developed a high throughput electrorefiner (HTER) that has a transport rate approximately three times faster than electrorefiners previously developed at ANL. This higher rate is due to the higher electrode surface area, a shorter transport path, and more efficient mixing, which leads to smaller boundary layers about the electrodes. This higher throughput makes electrorefining an attractive option in treating Department of Energy spent nuclear fuels. Experiments have been done to characterize the HTER, and a simulant metallic fuel has been successfully treated. The HTER design and experimental results is discussed

  13. Feasibility of megavoltage portal CT using an electronic portal imaging device (EPID) and a multi-level scheme algebraic reconstruction technique (MLS-ART)

    International Nuclear Information System (INIS)

    Guan, Huaiqun; Zhu, Yunping

    1998-01-01

    Although electronic portal imaging devices (EPIDs) are efficient tools for radiation therapy verification, they only provide images of overlapped anatomic structures. We investigated using a fluorescent screen/CCD-based EPID, coupled with a novel multi-level scheme algebraic reconstruction technique (MLS-ART), for a feasibility study of portal computed tomography (CT) reconstructions. The CT images might be useful for radiation treatment planning and verification. We used an EPID, set it to work at the linear dynamic range and collimated 6 MV photons from a linear accelerator to a slit beam of 1 cm wide and 25 cm long. We performed scans under a total of ∼200 monitor units (MUs) for several phantoms in which we varied the number of projections and MUs per projection. The reconstructed images demonstrated that using the new MLS-ART technique megavoltage portal CT with a total of 200 MUs can achieve a contrast detectibility of ∼2.5% (object size 5mmx5mm) and a spatial resolution of 2.5 mm. (author)

  14. Development of an efficient and economic small scale management scheme for low-and intermediate level radioactive waste and its impact on the environment

    International Nuclear Information System (INIS)

    Salomon, A.Ph.; Panem, J.A.; Manalastas, H.C.; Cortez, S.L.; Paredes, C.H.; Bartolome, Z.M.

    1976-05-01

    This paper is a preliminary report on the evolution of a pilot-scale management system for low-and intermediate level radioactive wastes to provide adequate protection to the public as well as maintain the equilibrium in the human environment. Discussions on the waste management and disposal scheme proposals, assessment of waste treatment requirements of the Atomic Research Center, Philippine Atomic Energy Commission, previous experiences in the handling and management of radioactive wastes, current practices and alternatives to meet waste management problems and research studies on waste treatment are presented. In the selection of a chemical treatment process for ARC, comparative studies on the different waste processing methods or combination of processes that will be most suitable for the waste requirements of the Center are now in progress. The decontamination efficiency and economy of the lime-soda, ferrocyanide phosphate and ferric hydroxide methods are being compared. Jar experiments were conducted in the Lime-Soda Process to establish the optima conditions for certain parameter required in order to achieve an efficient and economical treatment system applicable to the local conditions for attaining maximum removal of contamination; maximum settling time - 5 hours after treatment, optimum pH-11, 2:3 ppm ratio of Ca +2 to Co 3 -2 concentration, concentration of dosing reagents can further be increased beyond 160 ppm Ca +2 and 240 ppm Co 3 -2 . Cobalt contamination can be removed with lime-soda treatment aside from strontium

  15. Study of dose levels absorbed by members of the public in the nuclear medicine departments

    International Nuclear Information System (INIS)

    Cabral, Geovanna Oliveira de Mello

    2001-03-01

    In nuclear Medicine, radioisotopes are bound to various compounds (called radiopharmaceuticals) for use in various diagnostic and therapeutic applications. These unsealed sources are administered in various forms to patients, who remain radioactive for hours or days, and represent a source of potential radiation exposure for others. Thus, in nuclear medicine departments, radiation protection of workers and members of the public, especially persons accompanying patients, must consider, this exposure. In Brazil, the Comissao Nacional de Energia Nuclear (CNEN) establishes that, in nuclear medicine departments, the patients and persons accompanying should be separated each other. However, this rule is not always followed due to many factors such as physical and emotional conditions of patients. In this context, the aim of this study was the investigation of dose levels, which the persons accompanying patients are exposed to. For monitoring, thermoluminescent dosimeters were employed. The dosimeters were given to 380 persons who were accompanying patients in nuclear medicine departments. Exposure results were lower than 1 mSv. On the basis of CNEN rules, issues regarding stay conditions for members of the public in these departments are discussed. (author)

  16. Modeling by GASP-IV simulation of high-level nuclear waste disposal

    International Nuclear Information System (INIS)

    Kurstedt, H.A. Jr.; DePorter, E.L.; Turek, J.L.; Funk, S.K.; Rasbach, C.E.

    1981-01-01

    High-level nuclear waste generated by defense-oriented and commercial nuclear energy activities are to be stored ultimately in underground repositories. Research continues on the waste-form and waste-form processing. DOE managers must coordinate the results of this research, the capacities and availability times of the permanent geologic storage repositories, and the capacities and availability times of interim storage facilities (pending availability of permanent repositories). Comprehensive and active DOE program-management information systems contain predicted generation of nuclear wastes from defense and commercial activities; milestones on research on waste-forms; and milestones on research and development, design, acquisition, and construction of facilities and repositories. A GASP IV simulation model is presented which interfaces all of these data. The model accepts alternate management decisions; relates all critical milestones, all research and development data, and the generation of waste nuclear materials; simulates the passage of time; then, predicts the impact of those alternate decisions on the availability of storage capacity for waste nuclear materials. 3 references, 3 figures

  17. Four themes that underlie the high-level nuclear waste management program

    International Nuclear Information System (INIS)

    Sprecher, W.M.

    1989-01-01

    In 1982, after years of deliberation and in response to mounting pressures from environmental, industrial, and other groups, the US Congress enacted the Nuclear Waste Policy Act (NWPA) of 1982, which was signed into law by the President in January 1983. That legislation signified a major milestone in the nation's management of high-level nuclear waste, since it represented a consensus among the nation's lawmakers to tackle a problem that had evaded solution for decades. Implementation of the NWPA has proven to be exceedingly difficult, as attested by the discord generated by the US Department of Energy's (DOE's) geologic repository and monitored retrievable storage (MRS) facility siting activities. The vision that motivated the crafters of the 1982 act became blurred as opposition to the law increased. After many hearings that underscored the public's concern with the waste management program, the Congress enacted the Nuclear Waste Policy Amendments Act of 1987 (Amendments Act), which steamlined and focused the program, while establishing three independent bodies: the MRS Review Commission, the Nuclear Waste Technical Review Board, and the Office of the Nuclear Waste Negotiator. Yet, even as the program evolves, several themes characterizing the nation's effort to solve the waste management problem continue to prevail. The first of these themes has to do with social consciousness, and the others that follow deal with technical leadership, public involvement and risk perceptions, and program conservatism

  18. Additive operator-difference schemes splitting schemes

    CERN Document Server

    Vabishchevich, Petr N

    2013-01-01

    Applied mathematical modeling isconcerned with solving unsteady problems. This bookshows how toconstruct additive difference schemes to solve approximately unsteady multi-dimensional problems for PDEs. Two classes of schemes are highlighted: methods of splitting with respect to spatial variables (alternating direction methods) and schemes of splitting into physical processes. Also regionally additive schemes (domain decomposition methods)and unconditionally stable additive schemes of multi-component splitting are considered for evolutionary equations of first and second order as well as for sy

  19. Transport of Spent Nuclear Fuels, High and Intermediate Level Wastes: A Continuous Challenge

    International Nuclear Information System (INIS)

    Otton, C.; Blachet, L.

    2009-01-01

    For more than 45 years TN International has been involved in the radioactive materials transportation field. Since the beginning the used nuclear fuel transportation has been its core business. During all these years TN International, now part of AREVA, has been able to anticipate and fulfil the needs for new transport or storage casks design to fit the nuclear industry evolutions. A whole fleet of casks able to transport all the materials of the nuclear fuel cycle has been developed. In this presentation we will focus on the casks for the spent fuel, high level waste and intermediate level waste transportation. Answering to the constant evolution of the nuclear industry transport needs is a challenge that TN International faces routinely. Concerning the spent nuclear fuel transportation, TN International has developed in the early 80's a fleet of TN12 type casks fitted with several types of baskets able to safely transport all the spent fuel from the nuclear power plant or the research laboratories to AREVA La Hague plant. The current challenge is the design of a new transport cask generation taking into account the needs of the industry for the next 30 years. The replacement of the TN12 cask generation is to be scheduled as the regulations have changed and the fuel characteristics have evolved. The new generation of casks will take into account all the technical evolutions made during the TN12 thirty years of use. MOX spent fuel has now its dedicated cask: the TN112 which certificate of approval has been obtained in July 2008. This cask is able to transport 12 MOX spent fuel elements with a short cooling time. The first loading of the cask has been performed in 2008 in the EDF nuclear power plant of Saint-Laurent-des-Eaux. Concerning the high level waste such as the La Hague vitrified residues a whole fleet of casks has been developed such as the TN 28 VT dedicated to transport, the TN81 and TN85 dedicated to transport and storage. These casks have permitted the

  20. The Fourier transform as a signature for chaos in nuclear energy levels

    International Nuclear Information System (INIS)

    Bybee, C.R.; Mitchell, G.E.; Shriner, J.F. Jr.

    1996-01-01

    The Fourier transform of the autocorrelation function is an alternative test to characterize level statistics. For GOE statistics there is a suppression of the Fourier transform near the origin; this correlation hole is absent for Poisson statistics. Numerical modeling has been used to quantify the method and determine the dependence of the correlation-hole area on number, density, sampling interval, and fraction of missing or spurious levels. For large N the normalized correlation-hole area is a nearly universal constant and insensitive to missing and spurious levels. However, for the smaller sample sizes typical of nuclear data, application of the FT method yields ambiguous results. (orig.)

  1. Method of levelized discounted costs applied in economic evaluation of nuclear power plant project

    International Nuclear Information System (INIS)

    Tian Li; Wang Yongqing; Liu Jingquan; Guo Jilin; Liu Wei

    2000-01-01

    The main methods of economic evaluation of bid which are in common use are introduced. The characteristics of levelized discounted cost method and its application are presented. The method of levelized discounted cost is applied to the cost calculation of a 200 MW nuclear heating reactor economic evaluation. The results indicate that the method of levelized discounted costs is simple, feasible and which is considered most suitable for the economic evaluation of various case. The method is suggested which is used in the national economic evaluation

  2. Thoughts of the nuclear safety culture and 'star-level' management

    International Nuclear Information System (INIS)

    Wang Sen

    2004-01-01

    From the point of view that enterprise management has come into the stage of cultural management, this article divides the contents of nuclear safety culture into target management, safety management, quality management, site management, cost management, authority management, teamwork, information communication and continuous improvement. Each aspect win be classified by five 'star- level's according to the appearance, and the present situation of the company should be assessed with those star-level indices so as to find out the disadvantages. Improvement will follow with the promotion of company management level. (author)

  3. The Fourier transform as a signature for chaos in nuclear energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Bybee, C.R. [North Carolina State Univ., Raleigh, NC (United States)]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Mitchell, G.E. [North Carolina State Univ., Raleigh, NC (United States)]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Shriner, J.F. Jr. [Tennessee Technological Univ., Cookeville (United States)

    1996-08-01

    The Fourier transform of the autocorrelation function is an alternative test to characterize level statistics. For GOE statistics there is a suppression of the Fourier transform near the origin; this correlation hole is absent for Poisson statistics. Numerical modeling has been used to quantify the method and determine the dependence of the correlation-hole area on number, density, sampling interval, and fraction of missing or spurious levels. For large N the normalized correlation-hole area is a nearly universal constant and insensitive to missing and spurious levels. However, for the smaller sample sizes typical of nuclear data, application of the FT method yields ambiguous results. (orig.)

  4. Determination of leveled costs of electric generation for gas plants, coal and nuclear; Determinacion de costos nivelados de generacion electrica para plantas de gas, carbon y nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Alonso V, G.; Palacios H, J.C.; Ramirez S, J.R.; Gomez, A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: galonso@nuclear.inin.mx

    2005-07-01

    The present work analyzes the leveled costs of electric generation for different types of nuclear reactors known as Generation III, these costs are compared with the leveled costs of electric generation of plants with the help of natural gas and coal. In the study several discount rates were used to determine their impact in the initial investment. The obtained results are comparable with similar studies and they show that it has more than enough the base of the leveled cost the nuclear option it is quite competitive in Mexico. Also in this study it is also thinks about the economic viability of a new nuclear power station in Mexico. (Author)

  5. Evaluation of safety issues on newly regulated nuclear power plant by tsunami-level 1 PRA

    International Nuclear Information System (INIS)

    Tsuji, Yutaro; Miwa, Shuichiro; Mori, Michitsugu

    2014-01-01

    The tsunami caused by the Great East Japan Earthquake triggered severe accidents involving the units 1 to 4 at the Fukushima Dai-ichi nuclear power station (NPS). In order to re-operate existing nuclear power plants it should be necessary to reduce the core damage frequency on risk by tsunami. In this work, effects of the off-site power supply installation on resuming operation of nuclear power plants were investigated by utilizing the Tsunami-Level 1 Probability Risk Assessment (PRA). Unit 2 of the Onagawa nuclear power station, which resembled units 2 and 3 of Fukushima Dai-ichi, was selected for PRA. First, event-tree was created for the units of the Onagawa nuclear power station with the safety systems such as Emergency Core Cooling System (ECCS), investigating the plant situation at the time of the earthquake and tsunami occurrences. It was assumed that the magnitude of the tsunami was equivalent to the Great East Japan Earthquake. The accident-analytical progression-time was 36 hours, determined from the core-damage occurrence of the unit 3 of Fukushima Dai-ichi nuclear power station. Failure probabilities were calculated by the fault tree, which was created from the elements listed in the event tree. For the calculation, failure rates reported by the NUCIA (NUClear Information Archives) were primarily utilized. Then, obtained failure probabilities were embedded to the event tree. Core damage probabilities were evaluated by calculating success and failure rates for each accidental progression and scenarios. Restoration of the failed equipment and machineries was not considered in the analysis. Installation of the power supply vehicles at the nuclear power plant site reduced the core damage probability from 2.58×10 -6 to 8.56×10 -7 . However, continued addition of the power supply vehicles could not lower the core damage probability further more. In the case of Unit 2 of Onagawa nuclear power station, there could be a limit to lower the core damage

  6. Low Level Event and Near Miss Process for Nuclear Power Plants: Best Practices

    International Nuclear Information System (INIS)

    2012-01-01

    The IAEA programme on the operational safety of nuclear power plants gives priority to the development and promotion of the proper use of IAEA safety standards through the provision of assistance to Member States in the application of safety standards, the performance of safety review missions and the conduct of training activities based on safety standards. A number of IAEA safety standards and nuclear safety publications discuss the processes that need to be put into place for the feedback and analysis of operating experience (OE) at nuclear power plants. These include: Fundamental Safety Principles (IAEA Safety Standards Series No. SF-1), Safety of Nuclear Power Plants: Commissioning and Operation (IAEA Safety Standards Series No. SSR-2/2), Application of the Management System for Facilities and Activities (IAEA Safety Standards Series No. GS-G-3.1) and A System for the Feedback of Experience from Events in Nuclear Installations (IAEA Safety Standards Series No. NS-G-2.11). Additionally, several IAEA TECDOCs cover many aspects of the establishment, conduct and continuous improvement of an OE programme at nuclear power plants, including the consideration of low level events (LLEs) and near misses (NMs). Although these IAEA safety standards and nuclear safety publications have been in existence for several years, 70 per cent of the IAEA Operational Safety Review Team (OSART) missions carried out at nuclear power plants between 2006 and 2010 identified weaknesses in the reporting and analysis process for LLEs and NMs. In fact, this has been one of the recurring issues most often identified in the area of OE during these missions. These weaknesses have been further confirmed by most of the IAEA Peer Review of the Operational Safety Performance Experience (PROSPER) missions that have been conducted to date. Finally, the IAEA International Nuclear Safety Group, in their report entitled Improving the International System for Operating Experience Feedback (INSAG-23

  7. Dynamic nuclear polarization at high Landau levels in a quantum point contact

    Science.gov (United States)

    Fauzi, M. H.; Noorhidayati, A.; Sahdan, M. F.; Sato, K.; Nagase, K.; Hirayama, Y.

    2018-05-01

    We demonstrate a way to polarize and detect nuclear spin in a gate-defined quantum point contact operating at high Landau levels. Resistively detected nuclear magnetic resonance (RDNMR) can be achieved up to the fifth Landau level and at a magnetic field lower than 1 T. We are able to retain the RDNMR signals in a condition where the spin degeneracy of the first one-dimensional (1D) subband is still preserved. Furthermore, the effects of orbital motion on the first 1D subband can be made smaller than those due to electrostatic confinement. This developed RDNMR technique is a promising means to study electronic states in a quantum point contact near zero magnetic field.

  8. Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B., E-mail: rpgm@cdtn.br, E-mail: reisas@cdtn.br, E-mail: gfk@cdtn.br, E-mail: esct@cdtn.br, E-mail: tco@cdtn.br, E-mail: ama@cdtn.br, E-mail: francom@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, {sup 3}H, {sup 14}C, {sup 55}Fe, {sup 59}Ni, {sup 63}Ni, {sup 90}Sr, {sup 93}Zr, {sup 94}Nb, {sup 99}Tc, {sup 129}I, {sup 235}U, {sup 238}U, {sup 238}Pu, {sup 239}+{sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 242}Cm e {sup 243}+{sup 244}Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

  9. Future health physics prospects in high-level nuclear waste management

    International Nuclear Information System (INIS)

    Waite, D.A.; Mayberry, J.J.

    1986-01-01

    The objective of this presentation is to provide an overview of health physics activities anticipated to be required at a high-level nuclear waste repository and to project the numbers of health physics personnel expected to be required to carry out these activities. Health physics personnel receiving consideration in the projections include the health physics manager, shift supervisors, area supervisors, health physicists, and technologists. Phases of the repository addressed are construction, operation, retrieval, and decommissioning. Specific topics discussed in the process of developing the projections are: (a) the basic features of a geologic repository, (b) the staffing requirements of such a repository, (c) health physics involvement in repository operations, and (d) the anticipated schedule for operation of repositories in the United States. A quantitative assessment of future health physics prospects in high-level nuclear waste management is included

  10. Application of PSA to Assess the Safety Level of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Berg, H. P.; Goertz, R.

    2000-01-01

    This paper reviews the application of PSA in German nuclear power plant regulation. From a fundamental point of view, it has to be mentioned that as stipulated in the corresponding requirements, regulatory decision making in Germany is primarily based on deterministic analyses and evaluations. Therefore, PSA is not used as a stand alone but as a supplementary basis. In this context PSA has developed a valuable tool with continuously growing importance. Level 1+ PSAs are now elaborated for all German nuclear power plants in operation, most of them are already reviewed by the competent supervisory authority and its experts. Current research activities on the federal level primarily concentrate on the further development of the methodology in the areas human factor, common cause failures, accident management measures and reduction of uncertainties in methods and data. (author)

  11. POPCYCLE: a computer code for calculating nuclear and fossil plant levelized life-cycle power costs

    International Nuclear Information System (INIS)

    Hardie, R.W.

    1982-02-01

    POPCYCLE, a computer code designed to calculate levelized life-cycle power costs for nuclear and fossil electrical generating plants is described. Included are (1) derivations of the equations and a discussion of the methodology used by POPCYCLE, (2) a description of the input required by the code, (3) a listing of the input for a sample case, and (4) the output for a sample case

  12. High-level waste solidification system for the Western New York Nuclear Service Center

    International Nuclear Information System (INIS)

    Carrell, J.R.; Holton, L.K.; Siemens, D.H.

    1982-01-01

    A preconceptual design for a waste conditioning and solidification system for the immobilization of the high-level liquid wastes (HLLW) stored at the Western New York Nuclear Service Center (WNYNSC), West Valley, New York was completed in 1981. The preconceptual design was conducted as part of the Department of Energy's (DOE) West Valley Demonstration Project, which requires a waste management demonstration at the WNYNSC. This paper summarizes the bases, assumptions, results and conclusions of the preconceptual design study

  13. Tentative job analysis for a high-level, fixed-site, nuclear security officer

    International Nuclear Information System (INIS)

    Adams, K.G.; Trujillo, A.A.

    1977-10-01

    A tentative job analysis for a high-level, fixed-site, nuclear security officer is presented. The primary objective of the report is to provide a framework for evaluating the functions of a security officer in physical protection systems. Several job requirements related to duties, basic skills, personal contacts, supervision, working conditions, and decision making are presented. Individual character traits desirable in security officers are described

  14. Environmental program planning for the proposed high-level nuclear waste repository at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    1987-08-01

    This report was prepared to illustrate the policy and actions that the State of Nevada believe are required to assure that the quality of the environment is adequately considered during the course of the DOE work at the proposed high-level nuclear waste repository at Yucca Mountain. The report describes the DOE environmental program and the studies planned by NWPO to reflect the State's position toward environmental protection. 41 refs., 2 figs., 11 tabs

  15. Low-level radioactive waste management in EDF nuclear power plants (FRANCE)

    International Nuclear Information System (INIS)

    Boussard, C.

    1991-01-01

    This paper shows some recent examples of Low-level radioactive waste management in EDF nuclear power plants: - Radioactive liquid wastes proceeding from steam generators leaching (NOGENT SUR SEINE-1 REACTOR) - Thermal insulation proceeding from heat exchanger and blower (CHINON-2 REACTOR) - Old iron from reactor dismantling (CHINON-3 REACTOR, MARCOULE G1 REACTOR, MARCOULE G2-G3 REACTORS) - fresh air filter and fire detector - CHINON-2 REACTOR breaker chambers

  16. An optimized approach towards the treatment of high level liquid waste in the nuclear cycle

    International Nuclear Information System (INIS)

    Maio, V.; Todd, T.; Law, J.; Roach, J.; Sabharwall, P.

    2006-01-01

    Full text: One key long-standing issue that must be overcome to realize the successful growth of nuclear power is an economical, politically acceptable, stakeholder-compatible, and technically feasible resolution pertaining to the safe treatment and disposal of high-level liquid radioactive waste (HLLW). In addition to spent nuclear reactor fuel, HLLW poses a unique challenge in regard to environmental and security concerns, since future scenarios for a next generation of domestic and commercialized nuclear fuel cycle infrastructures must include reprocessing - the primary source of HLLW-to ensure the cost effectiveness of nuclear power as well as mitigate any threats as related to proliferation. Past attempts to immobilize HLLW - generated by both the weapons complex and the commercial power sector-have been plagued by an inability to convince the public and some technical peer reviewers that any proposed geological disposal sites (e.g., Yucca Mountain) can accommodate and contain the HLLW for a period of geological time equivalent to ten fold the radiological half-life of the longest lived of the actinides remaining after reprocessing. The paper explores combined equipment and chemical processing approaches for advancing and economizing the immobilization of high level liquid waste to ensure its long term durability, its decoupling from the unknown behavior of the repository over long geological time periods, and its economical formulation as required for the nuclear fuel cycle of the future. One approach involves the investigation of crystalline based waste forms as opposed to the glass/amorphous based waste forms, and how recent developments in crystalline forms show promise in sequestering the long lived actinides for over tens of millions of years. Another approach -compatible with the first- involves the use of an alternative melter technology-the Cold Crucible Induction Melter (CCIM)- to overcome the engineering material problems of Joule Heated Meters (JHM

  17. Robotics and remote handling concepts for disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    McAffee, Douglas; Raczka, Norman; Schwartztrauber, Keith

    1997-01-01

    This paper summarizes preliminary remote handling and robotic concepts being developed as part of the US Department of Energy's (DOE) Yucca Mountain Project. The DOE is currently evaluating the Yucca Mountain Nevada site for suitability as a possible underground geologic repository for the disposal of high level nuclear waste. The current advanced conceptual design calls for the disposal of more than 12,000 high level nuclear waste packages within a 225 km underground network of tunnels and emplacement drifts. Many of the waste packages may weigh as much as 66 tonnes and measure 1.8 m in diameter and 5.6 m long. The waste packages will emit significant levels of radiation and heat. Therefore, remote handling is a cornerstone of the repository design and operating concepts. This paper discusses potential applications areas for robotics and remote handling technologies within the subsurface repository. It also summarizes the findings of a preliminary technology survey which reviewed available robotic and remote handling technologies developed within the nuclear, mining, rail and industrial robotics and automation industries, and at national laboratories, universities, and related research institutions and government agencies

  18. Ceramic process and plant design for high-level nuclear waste immobilization

    International Nuclear Information System (INIS)

    Grantham, L.F.; McKisson, R.L.; De Wames, R.E.; Guon, J.; Flintoff, J.F.; McKenzie, D.E.

    1983-01-01

    In the last 3 years, significant advances in ceramic technology for high-level nuclear waste solidification have been made. Product quality in terms of leach-resistance, compositional uniformity, structural integrity, and thermal stability promises to be superior to borosilicate glass. This paper addresses the process effectiveness and preliminary designs for glass and ceramic immobilization plants. The reference two-step ceramic process utilizes fluid-bed calcination (FBC) and hot isostatic press (HIP) consolidation. Full-scale demonstration of these well-developed processing steps has been established at DOE and/or commercial facilities for processing radioactive materials. Based on Savannah River-type waste, our model predicts that the capital and operating cost for the solidification of high-level nuclear waste is about the same for the ceramic and glass options. However, when repository costs are included, the ceramic option potentially offers significantly better economics due to its high waste loading and volume reduction. Volume reduction impacts several figures of merit in addition to cost such as system logistics, storage, transportation, and risk. The study concludes that the ceramic product/process has many potential advantages, and rapid deployment of the technology could be realized due to full-scale demonstrations of FBC and HIP technology in radioactive environments. Based on our finding and those of others, the ceramic innovation not only offers a viable backup to the glass reference process but promises to be a viable future option for new high-level nuclear waste management opportunities

  19. Retrievability of high level waste and spent nuclear fuel. Proceedings of an international seminar

    International Nuclear Information System (INIS)

    2000-12-01

    The possibility of retrieving spent nuclear fuel or reprocessing high-level radioactive wastes placed in geological repositories is an issue that has attracted increased attention during the past few years, not only among technical experts but also among politicians at different levels, environmental organisations and other interested representatives of the public. This publication contains the presented invited papers, an edited record of the discussions and some concluding remarks. The seminar addressed a wide range of aspects of retrievability including technical options; public acceptance; ethical aspects; long term monitoring and cost considerations; safety and regulatory aspects. Each of the presented papers was indexed separately

  20. Status of commercial nuclear high-level waste disposal. Special report

    International Nuclear Information System (INIS)

    Dau, G.J.; Williams, R.F.

    1976-09-01

    The results of this review, presented in the form of a functional description of high level waste management system, shows that technology is available to dispose of nuclear waste safely by several different processes. The most attractive alternative in terms of available technology and shortness of time to demonstrate it at commercial scale is a system that converts the waste to a solid by immobilizing the radioactive elements in a glass matrix. Brief comments are also given on international efforts in high level waste management and advanced disposal concepts

  1. Levels of surface contamination with radioactive materials at workplaces of nuclear research centre at Rez

    International Nuclear Information System (INIS)

    Hoelgye, Z.; Nemcova, I.; Kasikova, M.; Popper, J.; Chysky, J.

    1983-01-01

    A hygiene supervision unit at workplaces of the nuclear Research Institute in Rez monitored on a long-term basis surface contamination with radioactive substances. Surface contamination was found at workplaces with open sources. Of the 4343 monitored places action levels were only exceeded in 13 cases. The obtained data were used for typifying workplaces with the highest level of surface contamination, to determine in certain instances the mechanism of the escape of radioactive substances from insulating facilities and to determine the rate of the spread of the radioactive substance into adjacent non-active workplaces. (author)

  2. Retrievability of high level waste and spent nuclear fuel. Proceedings of an international seminar

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    The possibility of retrieving spent nuclear fuel or reprocessing high-level radioactive wastes placed in geological repositories is an issue that has attracted increased attention during the past few years, not only among technical experts but also among politicians at different levels, environmental organisations and other interested representatives of the public. This publication contains the presented invited papers, an edited record of the discussions and some concluding remarks. The seminar addressed a wide range of aspects of retrievability including technical options; public acceptance; ethical aspects; long term monitoring and cost considerations; safety and regulatory aspects. Each of the presented papers was indexed separately.

  3. High level nuclear waste repository in salt: Sealing systems status and planning report: Draft report

    International Nuclear Information System (INIS)

    1985-09-01

    This report documents the initial conceptual design studies for a repository sealing system for a high-level nuclear waste repository in salt. The first step in the initial design studies was to review the current design level, termed schematic designs. This review identified practicality of construction and development of a design methodology as two key issues for the conceptual design. These two issues were then investigated during the initial design studies for seal system materials, seal placement, backfill emplacement, and a testing and monitoring plan. The results of these studies have been used to develop a program plan for completion of the sealing system conceptual design. 60 refs., 26 figs., 18 tabs

  4. Risk perception on management of nuclear high-level and transuranic waste storage

    Energy Technology Data Exchange (ETDEWEB)

    Dees, Lawrence A. [Colorado Christian Univ., Lakewood, CO (United States)

    1994-08-15

    The Department of Energy`s program for disposing of nuclear High-Level Waste (HLW) and transuranic (TRU) waste has been impeded by overwhelming political opposition fueled by public perceptions of actual risk. Analysis of these perceptions shows them to be deeply rooted in images of fear and dread that have been present since the discovery of radioactivity. The development and use of nuclear weapons linked these images to reality and the mishandling of radioactive waste from the nations military weapons facilities has contributed toward creating a state of distrust that cannot be erased quickly or easily. In addition, the analysis indicates that even the highly educated technical community is not well informed on the latest technology involved with nuclear HLW and TRU waste disposal. It is not surprising then, that the general public feels uncomfortable with DOE`s management plans for with nuclear HLW and TRU waste disposal. Postponing the permanent geologic repository and use of Monitored Retrievable Storage (MRS) would provide the time necessary for difficult social and political issues to be resolved. It would also allow time for the public to become better educated if DOE chooses to become proactive.

  5. Sorption of strontium on uranyl peroxide: implications for a high-level nuclear waste repository.

    Science.gov (United States)

    Sureda, Rosa; Martínez-Lladó, Xavier; Rovira, Miquel; de Pablo, Joan; Casas, Ignasi; Giménez, Javier

    2010-09-15

    Strontium-90 is considered the most important radioactive isotope in the environment and one of the most frequently occurring radionuclides in groundwaters at nuclear facilities. The uranyl peroxide studtite (UO2O2 . 4H2O) has been observed to be formed in spent nuclear fuel leaching experiments and seems to have a relatively high sorption capacity for some radionuclides. In this work, the sorption of strontium onto studtite is studied as a function of time, strontium concentration in solution and pH. The main results obtained are (a) sorption is relatively fast although slower than for cesium; (b) strontium seems to be sorbed via a monolayer coverage of the studtite surface, (c) sorption has a strong dependence on ionic strength, is negligible at acidic pH, and increases at neutral to alkaline pH (almost 100% of the strontium in solution is sorbed above pH 10). These results point to uranium secondary solid phase formation on the spent nuclear fuel as an important mechanism for strontium retention in a high-level nuclear waste repository (HLNW). Copyright 2010 Elsevier B.V. All rights reserved.

  6. Risk perception on management of nuclear high-level and transuranic waste storage

    International Nuclear Information System (INIS)

    Dees, L.A.

    1994-01-01

    The Department of Energy's program for disposing of nuclear High-Level Waste (HLW) and transuranic (TRU) waste has been impeded by overwhelming political opposition fueled by public perceptions of actual risk. Analysis of these perceptions shows them to be deeply rooted in images of fear and dread that have been present since the discovery of radioactivity. The development and use of nuclear weapons linked these images to reality and the mishandling of radioactive waste from the nations military weapons facilities has contributed toward creating a state of distrust that cannot be erased quickly or easily. In addition, the analysis indicates that even the highly educated technical community is not well informed on the latest technology involved with nuclear HLW and TRU waste disposal. It is not surprising then, that the general public feels uncomfortable with DOE's management plans for with nuclear HLW and TRU waste disposal. Postponing the permanent geologic repository and use of Monitored Retrievable Storage (MRS) would provide the time necessary for difficult social and political issues to be resolved. It would also allow time for the public to become better educated if DOE chooses to become proactive

  7. Determination of 93Zr in medium and low level radioactive wastes from Brazilian nuclear power plants

    International Nuclear Information System (INIS)

    Oliveira, Thiago C.; Oliveira, Arno H.

    2015-01-01

    The majority of long-lived radionuclides produced in the nuclear power plants can be regarded as difficult-to-measure radionuclides (RDM), hence chemical separation is necessary before the nuclear measurement of them. The zirconium isotope 93 Zr is a long-lived pure β-particle-emitting radionuclide produced from 235 U fission and from neutron activation of the stable isotope 92 Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half-life, 93 Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Two different methodologies based on extractive resins and LSC and ICP-MS techniques that enables the 93 Zr determination in medium (ILW) and low level (LLW) radioactive wastes samples from Brazilian nuclear power plants has been developed in our laboratory. Analyzing real samples 65% and 75% chemical yields for 93 Zr recovery were achieved for ICP-MS and LSC techniques, respectively. The detection limits were 0.045 μg.L -1 for ICP-MS and 0.05 Bq.L -1 for LSC techniques. (author)

  8. Sequential injection/bead injection lab-on-valve schemes for on-line solid phase extraction and preconcentration of ultra-trace levels of heavy metals with determination by ETAAS and ICPMS

    DEFF Research Database (Denmark)

    Wang, Jianhua; Hansen, Elo Harald; Miró, Manuel

    2003-01-01

    are focused on the applications of SI-BI-LOV protocols for on-line microcolumn based solid phase extraction of ultra-trace levels of heavy metals, employing the so-called renewable surface separation and preconcentration manipulatory scheme. Two types of sorbents have been employed as packing material...

  9. Nuclear Data Sheets for A=213

    International Nuclear Information System (INIS)

    Basunia, M.S.

    2007-01-01

    Evaluated spectroscopic data and level schemes from radioactive decay and nuclear reaction studies are presented for all nuclei with mass number A=213. This evaluation for A=213 supersedes the earlier one by Y. A. Akovali (1992Ak01), published in Nuclear Data Sheets 66, 237 (1992)

  10. Nuclear level densities with pairing and self-consistent ground-state shell effects

    CERN Document Server

    Arnould, M

    1981-01-01

    Nuclear level density calculations are performed using a model of fermions interacting via the pairing force, and a realistic single particle potential. The pairing interaction is treated within the BCS approximation with different pairing strength values. The single particle potentials are derived in the framework of an energy-density formalism which describes self-consistently the ground states of spherical nuclei. These calculations are extended to statistically deformed nuclei, whose estimated level densities include rotational band contributions. The theoretical results are compared with various experimental data. In addition, the level densities for several nuclei far from stability are compared with the predictions of a back-shifted Fermi gas model. Such a comparison emphasizes the possible danger of extrapolating to unknown nuclei classical level density formulae whose parameter values are tailored for known nuclei. (41 refs).

  11. A model predictive controller for the water level of nuclear steam generators

    International Nuclear Information System (INIS)

    Na, Man Gyun

    2001-01-01

    In this work, the model predictive control method was applied to a linear model and a nonlinear model of steam generators. The parameters of a linear model for steam generators are very different according to the power levels. The model predictive controller was designed for the linear steam generator model at a fixed power level. The proposed controller designed at the fixed power level showed good performance for any other power levels by changing only the input-weighting factor. As the input-weighting factor usually increases, its relative stability does so. The stem generator has some nonlinear characteristics. Therefore, the proposed algorithm has been implemented for a nonlinear model of the nuclear steam generator to verify its real performance and also, showed good performance. (author)

  12. Development of national level preparedness for response to nuclear and radiological emergencies

    International Nuclear Information System (INIS)

    Pradeepkumar, K.S.

    2014-01-01

    In India, DAE being the nodal agency for technical support for response to any radiation emergency nuclear disaster and various nuclear and radiological emergency scenarios and their impacts are identified. To reduce their consequences development of methodologies for detection and quick impact assessment, trained First Responders and Quick Response Teams (QRTs), twenty two DAE Emergency Response Centers, mobile and aerial radiation monitoring systems, aerial and ground based validation trials etc. are carried out. Study related to radiological threats and simulated RDD experiments conducted using stable isotopes indicates that radiation levels for distances more than 50 m will not be very high as hotspots may be restricted to nearby area. The biggest challenge from an RDD explosion will be handling of the radioactive contamination and 'fear factor' compared to radiation exposure to public or First Responders. Level and pattern of radioactive contamination on ground following releases during nuclear accidents and minimum strength of orphan radioactive sources to be detected are taken into account for optimizing systems and monitoring methodology required for emergency preparedness

  13. Nuclear Data for Reactor Physics: Cross sections and level densities in the actinide region

    Directory of Open Access Journals (Sweden)

    Bernstein L.

    2010-03-01

    Full Text Available Nuclear data in the actinide region are particularly important because they are basis behind all simulations of nuclear reactor core behaviour over both long time scales (fuel depletion and waste production and short time scales (accident scenarios. Nuclear reaction cross sections must be known as precisely as possible so that core reaction rates can be accurately calculated. Although cross section measurements in this region have been widely performed, for certain nuclei, particularly those with short half lives, direct measurements are either very difficult or impossible and thus reactor simulations must rely on theoretical calculations or extrapolations from neighbouring nuclei. The greatest uncertainty in theoretical cross section calculations comes from the lack of knowledge of level densities, for which predicted values can often be incorrect by a factor of two or more. Therefore there is a strong case for a systematic experimental study of level densities in the actinide region for the purpose of a providing a stringent test of theoretical cross section calculations for nuclei where experimental cross section data are available and b for providing better estimations of cross sections for nuclei in which no cross section data are available.

  14. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, Barry D. (Dept. of Social Sciences, Michigan Technological Univ., Houghton (United States)), e-mail: bdsolomo@mtu.edu; Andren, Mats; Strandberg, Urban (Center for Public Sector Research, Univ. of Goeteborg, Goeteborg (Sweden))

    2010-09-15

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  15. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    International Nuclear Information System (INIS)

    Solomon, Barry D.; Andren, Mats; Strandberg, Urban

    2010-09-01

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  16. Management of commercial high-level nuclear waste in the United States

    International Nuclear Information System (INIS)

    Mann, S.A.

    1981-01-01

    The Nuclear Waste Policy Act of 1982 (Act), enacted by the 97th Congress in December and signed into law on Jan 7, 1983, by President Reagan, brings a whole new perspective to the nation's nuclear waste management effort. An elaborate set of near-term requirements and actions have to be accomplished within the first 180 days of this Act. As an initial step, Secretary of Energy Donald P. Hodel has established a Nuclear Waste Policy Act (NWPA) project office. The director of the NWPA project office, Robert L. Morgan, is responsible for the department's initial activities to implement the Act until the Office of Civilian Radioactive Waste Management, established by Section 304 of the Act, is activated. The Act requires major efforts in two primary areas: disposal and storage of spent fuel and high-level waste. Efforts in the former area are to be financed by fees collected from utilities and placed into a Nuclear Waste Fund for disposal services. The Act provides for federal storage of up to 1900 tons of spent fuel for those utilities that the Nuclear Regulatory Commission (NRC) determines cannot reasonably provide sufficient additional on-site storage. This federal storage is to be financed through utility-user fees that are placed into an Interim Storage Fund. The Act also provides for cooperative research, development, and demonstration activities at utility sites and federal sites. These activities are to be jointly funded by the utilities and the federal government. Lastly, there are generic research and development (RandD) activities in the spent fuel area that are funded from general appropriations. Mandated milestones have been established by the Act in the areas of gologic repository, fund management, monitored retrievable storage, and spent fuel storage

  17. A level III PSA for the inherently safe CAREM-25 nuclear power station

    International Nuclear Information System (INIS)

    Baron, Jorge H.; Nunez McLeod, J.; Rivera, S.S.

    2000-01-01

    A Level III PSA has been performed for the inherently safe CAREM-25 nuclear power station, as a requirement for licensing according to argentinian regulations. The CAREM-25 project is still at a detailed design state, therefore only internal events have been considered, and a representative site has been assumed for dose estimations. Several conservative hypothesis have been formulated, but even so an overall core melt frequency of 2.3E -5 per reactor year has been obtained. The risk estimations comply with the regulations. The risk values obtained are compared to the 700MW(e) nuclear power plant Atucha II PSA result, showing an effective risk reduction not only in the severe accident probability but alto in the consequence component of the risk estimation. (author)

  18. United States Program on Spent Nuclear Fuel and High-Level Radioactive Waste Management

    International Nuclear Information System (INIS)

    Stewart, L.

    2004-01-01

    The President signed the Congressional Joint Resolution on July 23, 2002, that designated the Yucca Mountain site for a proposed geologic repository to dispose of the nation's spent nuclear fuel (SNF) and high-level radioactive waste (HLW). The United States (U.S.) Department of Energy's (DOE) Office of Civilian Radioactive Waste Management (OCRWM) is currently focusing its efforts on submitting a license application to the U.S. Nuclear Regulatory Commission (NRC) in December 2004 for construction of the proposed repository. The legislative framework underpinning the U.S. repository program is the basis for its continuity and success. The repository development program has significantly benefited from international collaborations with other nations in the Americas

  19. Nuclear database management systems

    International Nuclear Information System (INIS)

    Stone, C.; Sutton, R.

    1996-01-01

    The authors are developing software tools for accessing and visualizing nuclear data. MacNuclide was the first software application produced by their group. This application incorporates novel database management and visualization tools into an intuitive interface. The nuclide chart is used to access properties and to display results of searches. Selecting a nuclide in the chart displays a level scheme with tables of basic, radioactive decay, and other properties. All level schemes are interactive, allowing the user to modify the display, move between nuclides, and display entire daughter decay chains

  20. Methodology for determining acceptable residual radioactive contamination levels at decommissioned nuclear facilities/sites

    International Nuclear Information System (INIS)

    Watson, E.C.; Kennedy, W.E. Jr.; Hoenes, G.R.; Waite, D.A.

    1979-01-01

    The ultimate disposition of decommissioned nuclear facilities and their surrrounding sites depends upon the degree and type of residual contamination. Examination of existing guidelines and regulations has led to the conclusion that there is a need for a general method to derive residual radioactive contamination levels that are acceptable for public use of any decommissioned nuclear facility or site. This paper describes a methodology for determining acceptable residual radioactive contamination levels based on the concept of limiting the annual dose to members of the public. It is not the purpose of this paper to recommend or even propose dose limits for the exposure of the public to residual radioactive contamination left at decommissioned nuclear facilities or sites. Unrestricted release of facilities and/or land is based on the premise that the potential annual dose to any member of the public using this property from all possible exposure pathways will not exceed appropriate limits as may be defined by Federal regulatory agencies. For decommissioned land areas, consideration should be given to people living directly on previously contaminated areas, growing crops, grazing food animals and using well water. Mixtures of radionuclides in the residual contamination representative of fuel reprocessing plants, light water reactors and their respective sites are presented. These mixtures are then used to demonstrate the methodology. Example acceptable residual radioactive contamination levels, based on an assumed maximum annual dose of one millirem, are calculated for several selected times following shutdown of a facility. It is concluded that the methodology presented in this paper results in defensible acceptable residual contamination levels that are directly relatable to risk assessment with the proviso that an acceptable limit to the maximum annual dose will be established. (author)

  1. Trending of low level events and near misses to enhance safety performance in nuclear power plants

    International Nuclear Information System (INIS)

    2005-11-01

    The IAEA Safety Fundamentals publication, Safety of Nuclear Installations, Safety Series No. 110, states the need for operating organizations to establish a programme for the collection and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, and lessons learned are disseminated to the staff of the organization and to relevant national and international organizations. As a result of the effort to enhance safety in operating organizations, incidents are progressively decreasing in number and significance. This means that in accordance with international reporting requirements the amount of collected data becomes less sufficient to draw meaningful statistical conclusions. This is where the collection and trend analysis of low level events and near misses can prove to be very useful. These trends can show which of the safety barriers are weak or failing more frequently. Evaluation and trending of low level events and near misses will help to prevent major incidents because latent weaknesses have been identified and corrective actions taken to prevent recurrence. This leads to improved safety and production. Low level events and near misses, which may reach several thousand per reactor operating year, need to be treated by the organizations as learning opportunities. A system for capturing these low level events and near misses truly needs to be an organization-wide system in which all levels of the organization, including contractors, participate. It is desirable that the overall operational experience feedback (OEF) process should integrate the lessons learned and the associated data from significant events with those of lower level events and near misses. To be able to effectively implement a process dealing with low level events and near misses, it is necessary that the organization have a well established OEF process for significant events

  2. Development and Application of Level 2 Probabilistic Safety Assessment for Nuclear Power Plants. Specific Safety Guide

    International Nuclear Information System (INIS)

    2010-01-01

    The objective of this Safety Guide is to provide recommendations for meeting the IAEA safety requirements in performing or managing a level 2 probabilistic safety assessment (PSA) project for a nuclear power plant; thus it complements the Safety Guide on level 1 PSA. One of the aims of this Safety Guide is to promote a standard framework, standard terms and a standard set of documents for level 2 PSAs to facilitate regulatory and external peer review of their results. It describes all elements of the level 2 PSA that need to be carried out if the starting point is a fully comprehensive level 1 PSA. Contents: 1. Introduction; 2. PSA project management and organization; 3. Identification of design aspects important to severe accidents and acquisition of information; 4. Interface with level 1 PSA: Grouping of sequences; 5. Accident progression and containment analysis; 6. Source terms for severe accidents; 7. Documentation of the analysis: Presentation and interpretation of results; 8. Use and applications of the PSA; Annex I: Example of a typical schedule for a level 2 PSA; Annex II: Computer codes for simulation of severe accidents; Annex III: Sample outline of documentation for a level 2 PSA study.

  3. Attempts to develop a new nuclear measurement technique of β-glucuronidase levels in biological samples

    International Nuclear Information System (INIS)

    Unak, T.; Avcibasi, U.; Yildirim, Y.; Cetinkaya, B.

    2003-01-01

    β-Glucuronidase is one of the most important hydrolytic enzymes in living systems and plays an essential role in the detoxification pathway of toxic materials incorporated into the metabolism. Some organs, especially liver and some tumour tissues, have high level of β-glucuronidase activity. As a result the enzymatic activity of some kind of tumour cells, the radiolabelled glucuronide conjugates of cytotoxic, as well as radiotoxic compounds have potentially very valuable diagnostic and therapeutic applications in cancer research. For this reason, a sensitive measurement of β-glucuronidase levels in normal and tumour tissues is a very important step for these kinds of applications. According to the classical measurement method of β-glucuronidase activity, in general, the quantity of phenolphthalein liberated from its glucuronide conjugate, i.e. phenolphthalein-glucuronide, by β-glucuronidase has been measured by use of the spectrophotometric technique. The lower detection limit of phenolphthalein by the spectrophotometric technique is about 1-3 mg. This means that the β-glucuronidase levels could not be detected in biological samples having lower levels of β-glucuronidase activity and therefore the applications of the spectrophotometric technique in cancer research are very seriously limited. Starting from this consideration, we recently attempted to develop a new nuclear technique to measure much lower concentrations of β-glucuronidase in biological samples. To improve the detection limit, phenolphthalein-glucuronide and also phenyl-N-glucuronide were radioiodinated with 131 I and their radioactivity was measured by use of the counting technique. Therefore, the quantity of phenolphthalein or aniline radioiodinated with 131 I and liberated by the deglucuronidation reactivity of β-glucuronidase was used in an attempt to measure levels lower than the spectrophotometric measurement technique. The results obtained clearly verified that 0.01 pg level of

  4. Nuclear level density effects on the evaluated cross-sections of nickel isotopes

    International Nuclear Information System (INIS)

    Garg, S.B.

    1995-01-01

    A detailed investigation has been made to estimate the effect of various level density options on the computed neutron induced reaction cross-sections of Ni-58 and Ni-60 covering the energy range 5-25 MeV in the framework of the multistep Hauser-Feshbach statistical model scheme which accounts for the pre-equilibrium decay according to the Kalbach exciton model and gamma-ray competition according to the giant dipole radiation model of Brink and Axel. Various level density options considered in this paper are based on the Original Gilbert-Cameron, Improved Gilbert-Cameron, Back-Shifted Fermi gas and the Ingatyuk-Smirenkin-Tishin approaches. The effect of these different level density prescriptions is brought out with special reference to (n,p) (n,2n) (n,α) and total production cross-sections for neutron, hydrogen, helium and gamma-rays which are of technological importance for fission and fusion based reactor systems. (author). 18 refs, 2 figs

  5. Progress on Plant-Level Components for Nuclear Fuel Recycling: Commonality

    International Nuclear Information System (INIS)

    De Almeida, Valmor F.

    2011-01-01

    Progress made in developing a common mathematical modeling framework for plant-level components of a simulation toolkit for nuclear fuel recycling is summarized. This ongoing work is performed under the DOE Nuclear Energy Advanced Modeling and Simulation (NEAMS) program, which has an element focusing on safeguards and separations (SafeSeps). One goal of this element is to develop a modeling and simulation toolkit for used nuclear fuel recycling. The primary function of the SafeSeps simulation toolkit is to enable the time-dependent coupling of separation modules and safeguards tools (either native or third-party supplied) that simulate and/or monitor the individual separation processes in a separations plant. The toolkit integration environment will offer an interface for the modules to register in the toolkit domain based on the commonality of diverse unit operations. This report discusses the source of this commonality from a combined mathematical modeling and software design perspectives, and it defines the initial basic concepts needed for development of application modules and their integrated form, that is, an application software. A unifying mathematical theory of chemical thermomechanical network transport for physicochemical systems is proposed and outlined as the basis for developing advanced modules. A program for developing this theory from the underlying first-principles continuum thermomechanics will be needed in future developments; accomplishment of this task will enable the development of a modern modeling approach for plant-level models. Rigorous, advanced modeling approaches at the plant-level can only proceed from the development of reduced (or low-order) models based on a solid continuum field theory foundation. Such development will pave the way for future programmatic activities on software verification, simulation validation, and model uncertainty quantification on a scientific basis; currently, no satisfactory foundation exists for

  6. Progress on Plant-Level Components for Nuclear Fuel Recycling: Commonality

    Energy Technology Data Exchange (ETDEWEB)

    de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2011-08-15

    Progress made in developing a common mathematical modeling framework for plant-level components of a simulation toolkit for nuclear fuel recycling is summarized. This ongoing work is performed under the DOE Nuclear Energy Advanced Modeling and Simulation (NEAMS) program, which has an element focusing on safeguards and separations (SafeSeps). One goal of this element is to develop a modeling and simulation toolkit for used nuclear fuel recycling. The primary function of the SafeSeps simulation toolkit is to enable the time-dependent coupling of separation modules and safeguards tools (either native or third-party supplied) that simulate and/or monitor the individual separation processes in a separations plant. The toolkit integration environment will offer an interface for the modules to register in the toolkit domain based on the commonality of diverse unit operations. This report discusses the source of this commonality from a combined mathematical modeling and software design perspectives, and it defines the initial basic concepts needed for development of application modules and their integrated form, that is, an application software. A unifying mathematical theory of chemical thermomechanical network transport for physicochemical systems is proposed and outlined as the basis for developing advanced modules. A program for developing this theory from the underlying first-principles continuum thermomechanics will be needed in future developments; accomplishment of this task will enable the development of a modern modeling approach for plant-level models. Rigorous, advanced modeling approaches at the plant-level can only proceed from the development of reduced (or low-order) models based on a solid continuum field theory foundation. Such development will pave the way for future programmatic activities on software verification, simulation validation, and model uncertainty quantification on a scientific basis; currently, no satisfactory foundation exists for

  7. Dose evaluation and establishment of reference levels in activity for nuclear medicine

    International Nuclear Information System (INIS)

    Ribeiro, Julio Cesar de Souza

    2017-01-01

    The International Commission on Radiation Protection (ICRP) has emphasized the importance of accurately determining the mean dose levels, or administered activity, received by the patients for each medical procedure that uses ionizing radiation. However, the number of bibliographic references addressing the need to know and optimize these levels is insufficient, or rather limited, which may lead to non-standardizes techniques, a lack of exposures control, and also the increase of associated radiological risks of these procedures. In this context, a software in Visual Basic® of Microsoft© language was developed whose function is to elaborate a method of obtaining the Reference Levels in Activity (RLA) for nuclear medicine patients by determining the third quartile of the examinations carried out. The program also allows obtaining absorbed dose values in critical organs based on patient specificities as age, sex and Body Mass Index (BMI) in order to evaluate the risk involved in each procedure. The main nuclear medicine diagnostic procedures were evaluated through the database of two public hospitals and a private clinic, obtaining the NRAs of each facility, where the software was validated by comparison with the traditionally accepted calculation methods. Due to the results obtained in each installation, in addition to NRA determination, gaps in treatment capacities and unjustified dose variations for the same procedure were identified, indicating the need for optimization. Thus, the developed program is able to provide the estimated values of effective and absorbed doses involved in each procedure, for each patient, providing reference values for nuclear medicine field, not available in the national scenario so far. (author)

  8. Receptor activator of nuclear factor kappa B ligand and osteoprotegerin levels in gingival crevicular fluid

    Science.gov (United States)

    Sarlati, Fatemeh; Sattari, Mandana; Razzaghi, Shilan; Nasiri, Malihe

    2012-01-01

    Background: Osteoclastogenesis is coordinated by the interaction of three members of the tumor necrosis factor (TNF) superfamily: Osteoprotegerin (OPG)/receptor activator of nuclear factor kappa B ligand (RANKL)/receptor activator of nuclear factor kappa B (RANK). The aim of this study was to investigate RANKL and OPG levels, and their relative ratio in gingival crevicular fluid (GCF) of patients with chronic and aggressive periodontitis, as well as healthy controls. Materials and Methods: In this analytical study, GCF was obtained from healthy (n = 10), mild chronic periodontitis (n = 18), moderate chronic periodontitis (n = 18), severe chronic periodontitis (n = 20), and generalized aggressive periodontitis (n = 20) subjects. RANKL and OPG concentrations were measured by enzyme-linked immunosorbent assay. Statistical tests used were Kruskal–Wallis test, Mann–Whitney U rank sum test, and Spearman's rank correlation analysis. The level of statistical significance was set at P chronic periodontitis (mild, moderate, severe), and aggressive periodontitis (P = 0.41). There was statistically significant correlation between the concentration of sRANKL and Clinical Attachment Level (CAL) in moderate chronic periodontitis patients (R = 0.48, P = 0.04). There was also negative correlation between OPG concentration and CAL in moderate chronic periodontitis patients, although not significant (R = −0.13). Conclusion: RANKL was prominent in periodontitis sites, especially in moderate periodontitis patients, whereas OPG was not detectable in some diseased sites with bleeding on probing, supporting the role of these two molecules in the bone loss developed in this disease. PMID:23559954

  9. A methodology for calculating the levelized cost of electricity in nuclear power systems with fuel recycling

    International Nuclear Information System (INIS)

    De Roo, Guillaume; Parsons, John E.

    2011-01-01

    In this paper we show how the traditional definition of the levelized cost of electricity (LCOE) can be extended to alternative nuclear fuel cycles in which elements of the fuel are recycled. In particular, we define the LCOE for a cycle with full actinide recycling in fast reactors in which elements of the fuel are reused an indefinite number of times. To our knowledge, ours is the first LCOE formula for this cycle. Others have approached the task of evaluating this cycle using an 'equilibrium cost' concept that is different from a levelized cost. We also show how the LCOE implies a unique price for the recycled elements. This price reflects the ultimate cost of waste disposal postponed through the recycling, as well as other costs in the cycle. We demonstrate the methodology by estimating the LCOE for three classic nuclear fuel cycles: (i) the traditional Once-Through Cycle, (ii) a Twice-Through Cycle, and (iii) a Fast Reactor Recycle. Given our chosen input parameters, we show that the 'equilibrium cost' is typically larger than the levelized cost, and we explain why.

  10. On the questions of the nuclear level density and the E1 photon strength functions

    International Nuclear Information System (INIS)

    Mughabghab, S.F.; Dunford, C.L.

    1999-01-01

    New results were derived from average level spacings of neutron resonances for the spin dispersion parameter of the nuclear level density, which demonstrated the influence of shell effects, as well as the interplay of nucleon pairing correlations for nuclei in the mass range from 29 Si to 241 Pu. The volume and surface components of the nuclear level density parameter, as well as the shell-damping factor, were determined as, a v = 0.076 ± 0.009 MeV -1 , a s = 0.180 ± 0.047 MeV -1 , and y 0 = 0.047 ± 0.04 MeV±, respectively. The effective nucleon mass at the Fermi surface is derived as m*/m = 1.09 ± 0.13. New evidence is presented for a dipole-quadrupole interaction term in the primary E1 transitions of average resonance capture data. This evidence is obtained by testing a proposed generalized Landau Fermi liquid model for spherical and deformed nuclei, which includes the effect of the dipole-quadrupole interaction. The Landau-Migdal interaction constant and the effective nucleon mass, are determined as F 0 prime = 1.49 ± 0.08, and m*/m=1.04 ± 0.07, respectively

  11. Recent Advances in Low-Level Nuclear Measurements at the CEA

    International Nuclear Information System (INIS)

    Mahe, C.; Lamadie, F.; Le Goaller, C.

    2009-01-01

    For several years the CEA has been performing nuclear measurements at different stages of decommissioning projects. The characterization tools initially developed for high-level radioactive waste analysis must be adapted to a new area of application: low-level measurements. Recent technical improvements in gamma imaging, gamma spectrometry detectors, and data analysis make it possible to provide relevant radiological data for waste management, as well as to develop robust and optimized decommissioning scenarios from the initial dose rate mapping to the final declared activity. These techniques have been implemented at various nuclear sites for both trial measurement campaigns and expert investigations to localize residual contamination, to identify the radioelements and to provide an accurate estimate of the declarable activity. Different types of measurements and devices have been used: gamma cameras, coded aperture techniques, alpha imaging prototypes, gamma spectrometry detectors (CdZnTe, HPGe, NaI, and LaBr 3 ), dose rate cartography, and calculation codes (Mercure, MCNP, etc.), all of which provide complementary data for radioactive waste categorization. This paper describes the latest developments and methods deployed on decommissioning projects focusing on low-level in situ applications. Waste drum characterization and in situ glove box measurements are discussed and the technologies and performance of gamma imaging systems, gamma spectrometry detectors, calculation codes and software are described. The paper concludes with a review of future developments and tests necessary for these applications. (authors)

  12. Should high-level nuclear waste be disposed of at geographically dispersed sites?

    International Nuclear Information System (INIS)

    Bassett, G.W. Jr.

    1992-01-01

    Consideration of the technical feasibility of Yucca Mountain in Nevada as the site for a high-level nuclear waste repository has led to an intense debate regarding the economic, social, and political impacts of the repository. Impediments to the siting process mean that the nuclear waste problem is being resolved by adhering to the status quo, in which nuclear waste is stored at scattered sites near major population centers. To assess the merits of alternative siting strategies--including both the permanent repository and the status quo- we consider the variables that would be included in a model designed to select (1) the optimal number of disposal facilities, (2) the types of facilities (e.g., permanent repository or monitored retrievable facility), and (3) the geographic location of storage sites. The objective function in the model is an all-inclusive measure of social cost. The intent of the exercise is not to demonstrate the superiority of any single disposal strategy; uncertainties preclude a conclusive proof of optimality for any of the disposal options. Instead, we want to assess the sensitivity of a variety of proposed solutions to variations in the physical, economic, political, and social variables that influence a siting strategy

  13. On-site storage of high level nuclear waste: Attitudes and perceptions of local residents

    International Nuclear Information System (INIS)

    Bassett, G.W. Jr.; Jenkins-Smith, H.C.; Silva, C.

    1996-01-01

    No public policy issue has been as difficult as high-level nuclear waste. Debates continue regarding Yucca Mountain as a disposal site, and - more generally - the appropriateness of geologic disposal and the need to act quickly. Previous research has focused on possible social, political, and economic consequences of a facility in Nevada. Impacts have been predicted to be potentially large and to emanate mainly from stigmatization of the region due to increased perceptions of risk. Analogous impacts from leaving waste at power plants have been either ignored or assumed to be negligible. This paper presents survey results on attitudes of residents in three countries where nuclear waste is currently stored. Topics include perceived risk, knowledge of nuclear waste and radiation, and impacts on jobs, tourism, and housing values from leaving waste on site. Results are similar to what has been reported for Nevada; the public is concerned about possible adverse effects from on-site storage of waste. 24 refs., 7 figs., 5 tabs

  14. Albedo Neutron Dosimetry in a Deep Geological Disposal Repository for High-Level Nuclear Waste.

    Science.gov (United States)

    Pang, Bo; Becker, Frank

    2017-04-28

    Albedo neutron dosemeter is the German official personal neutron dosemeter in mixed radiation fields where neutrons contribute to personal dose. In deep geological repositories for high-level nuclear waste, where neutrons can dominate the radiation field, it is of interest to investigate the performance of albedo neutron dosemeter in such facilities. In this study, the deep geological repository is represented by a shielding cask loaded with spent nuclear fuel placed inside a rock salt emplacement drift. Due to the backscattering of neutrons in the drift, issues concerning calibration of the dosemeter arise. Field-specific calibration of the albedo neutron dosemeter was hence performed with Monte Carlo simulations. In order to assess the applicability of the albedo neutron dosemeter in a deep geological repository over a long time scale, spent nuclear fuel with different ages of 50, 100 and 500 years were investigated. It was found out, that the neutron radiation field in a deep geological repository can be assigned to the application area 'N1' of the albedo neutron dosemeter, which is typical in reactors and accelerators with heavy shielding. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Nuclear and Particle Physics Simulations: The Consortium of Upper-Level Physics Software

    Science.gov (United States)

    Bigelow, Roberta; Moloney, Michael J.; Philpott, John; Rothberg, Joseph

    1995-06-01

    The Consortium for Upper Level Physics Software (CUPS) has developed a comprehensive series of Nine Book/Software packages that Wiley will publish in FY `95 and `96. CUPS is an international group of 27 physicists, all with extensive backgrounds in the research, teaching, and development of instructional software. The project is being supported by the National Science Foundation (PHY-9014548), and it has received other support from the IBM Corp., Apple Computer Corp., and George Mason University. The Simulations being developed are: Astrophysics, Classical Mechanics, Electricity & Magnetism, Modern Physics, Nuclear and Particle Physics, Quantum Mechanics, Solid State, Thermal and Statistical, and Wave and Optics.

  16. Overall review strategy for the Nuclear Regulatory Commission's High-Level Waste Repository Program

    International Nuclear Information System (INIS)

    Johnson, R.L.

    1994-11-01

    The Overall Review Strategy gives general guidance to the Nuclear Regulatory Commission staff for conducting it's license application and pre-license application reviews. These reviews are in support of the Commission's construction authorization decision for a geologic repository for the disposal of high-level radioactive waste. Objectives and strategies are defined that focus the staff's reviews on determining compliance with requirements of 10 CFR Part 60. These strategies define how the staff prioritizes its reviews on those key technical uncertainties considered to be most important to repository performance. Strategies also give guidance for developing, in an integrated way, the License Application Review Plan together with supporting performance assessments, analyses, and research

  17. Ecological risk assessment of deep geological disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    Hart, D.R.; Lush, D.L.; Acton, D.W.

    1993-01-01

    Contaminant fate and transport models, radiological dosimetry models, chemical dose-response models and population dynamic models were used to estimate ecological risks to moose and brook trout populations arising from a proposed high-level nuclear waste repository. Risks from potential contaminant releases were compared with risks from physical habitat alteration in constructing a repository and service community, and with risks from increased hunting and fish pressure in the area. For a reference environment typical of a proposed location somewhere in the Canadian Shield, preliminary results suggest that the population consequences of contaminant release will be minor relative to those of habitat alteration and natural resource use

  18. Multi-level governance-perspective on management of nuclear waste disposal. A comparative analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brunnengraeber, Achim; Haefner, Daniel

    2015-07-01

    The primary aim of the project is to conduct a detailed social and political analysis of the preconditions for the development of an acceptable strategy for nuclear waste disposal in Germany. This includes the identification of stakeholders and their interests, responsibilities, value systems, views and expectations as well as paths for a constructive approach to dialogue and problem-solving. A focus of the research project will be an international comparative multi-level governance analysis of acceptance patterns and steering mechanisms for conflict resolution.

  19. Canada's high-level nuclear waste disposal concept and its evaluation process

    International Nuclear Information System (INIS)

    Sheng, Grant; Shemilt, L.W.

    2004-01-01

    The concept of disposing high-level nuclear waste in granitic rocks in the Canadian Shield, developed by Atomic Energy of Canada Limited (AECL), is anticipated to undergo a national public review within two years. The disposal concept, its documentation, and its process of evaluation, including the role of the public, government and the scientific/engineering community, are summarized. A Technical Advisory Committee (TAC) has provided external peer review of the Program since 1979 and its findings are published in annual reports which are publicly available. (author)

  20. Microwave energy for post-calcination treatment of high-level nuclear wastes

    International Nuclear Information System (INIS)

    Gombert, D.; Priebe, S.J.; Berreth, J.R.

    1980-01-01

    High-level radioactive wastes generated from nuclear fuel reprocessing require treatment for effective long-term storage. Heating by microwave energy is explored in processing of two possible waste forms: (1) drying of a pelleted form of calcined waste; and (2) vitrification of calcined waste. It is shown that residence times for these processes can be greatly reduced when using microwave energy rather than conventional heating sources, without affecting product properties. Compounds in the waste and in the glass frit additives couple very well with the 2.45 GHz microwave field so that no special microwave absorbers are necessary

  1. The systems approach to spent fuel and high level nuclear waste management

    International Nuclear Information System (INIS)

    Norman, N.A.

    1987-01-01

    Based on the prior successful experience in the application of systems engineering techniques to large, complex, multi-participant programs the U.S. DOE has elected to apply the systems engineering process to the U.S. High Level Nuclear Waste Management Program (HLNWMP). Features of the systems engineering process as it applies to the U.S. HLNWMP and the importance of the component interdependencies are descirbed. Four principle components of the U.S. HLW Managment System are also given. They are the reactors or defense sources, transportation system, interium storoge modes, and the final repository. (Huang)

  2. Multi-level governance-perspective on management of nuclear waste disposal. A comparative analysis

    International Nuclear Information System (INIS)

    Brunnengraeber, Achim; Haefner, Daniel

    2015-01-01

    The primary aim of the project is to conduct a detailed social and political analysis of the preconditions for the development of an acceptable strategy for nuclear waste disposal in Germany. This includes the identification of stakeholders and their interests, responsibilities, value systems, views and expectations as well as paths for a constructive approach to dialogue and problem-solving. A focus of the research project will be an international comparative multi-level governance analysis of acceptance patterns and steering mechanisms for conflict resolution.

  3. Legal and judicial perspectives on the disposal of high-level nuclear waste

    International Nuclear Information System (INIS)

    Muntzing, L.M.

    1985-01-01

    Nuclear Waste Policy Act of 1982 creates a maze of legal requirements that are complex and subject to differing interpretations. The intervention of the courts should be anticipated as varying interests dispute the correct path through the maze to high-level waste disposal. A significant number of legal issues and unsettled questions exist that will need to be resolved. The challenge will be to minimize the delays that legal conflicts can produce. This can be helped by resolving uncertainties and conflicts early before they are on the critical path or negotiating resolutions, normally a difficult and costly endeavor

  4. The socioeconomic impacts of high-level nuclear waste facility siting

    International Nuclear Information System (INIS)

    Murdock, S.H.; Leistritz, F.L.; Hamm, R.R.

    1987-01-01

    High-level nuclear waste repositories will be located in sparsely settled rural areas in the U.S. These projects will significantly effect the economic, demographic, public service, fiscal, and social (the socioeconomic) dimensions of those rural areas. This paper examines some of the potential socioeconomic impacts and the characteristics of mitigation programs necessary, if these impacts are to be addressed. Both standard impacts, those resulting from the fact that--like many other large-scale developments--repositories will involve a substantial number of new workers and residents (relative to the size of existing communities) and special impacts, those resulting from the fact that repositories store radioactive materials, are examined

  5. Comparative study of the base activity levels of the Spanish continental nuclear power stations

    International Nuclear Information System (INIS)

    Gregorides de los Santos y Perez-Minguez, A.M.

    1980-01-01

    In this work the pre-operational activity levels of the sites of some Spanish nuclear power stations are discussed. These power stations are located near the Tagus and Ebro river basins. A report of the communities investigated is made. The total alpha and beta activity as well as the long half life activity has been researched there. The importance of this question is obvious for it gives a regional average of the base activity in the basins of these two big Spanish rivers [fr

  6. The Competence Promoting by NNSA for Keeping High Level Nuclear Safety: The Corner Stone of the Nuclear Safety Regulation Edifice

    International Nuclear Information System (INIS)

    Hu, L.

    2016-01-01

    Facing the fast development of the nuclear power industry and the application of radioactive sources, The MEP(NNSA) is endeavoured to promoting its competency, including: complementing the law system, training and recruiting staff to keep a capable team, constructing the R&D base to keep the basic capability, promoting safety culture both for the industry and the regulator. After the Fukushima nuclear accident, the MEP(NNSA) planned to construct R&D base, in which the Platform Nuclear Safety Monitoring and Emergency Responding, the Platform of Safety Technology of PWR Testing, the Laboratory of Safety Management Technology of Nuclear Waste Verification, the Laboratory of Environmental Radiation Monitoring and the Center of International Cooperation are included. On the other hand, the MEP(NNSA) issued Chinese nuclear safety culture policy declaration in 2014, and carried out a large scale Specialized Action for Nuclear Safety Promotion to promote the nuclear safety culture both for the industry and herself. For the nuclear regulator, It is essential to conduct the competence promoting by both “hardware” and “software”, the former is the material foundation of regulation authority, which will be effectively functioning under the facilitating of the latter. (author)

  7. Analysis of data related to the updating of diagnosis reference levels in radiology and nuclear medicine. Assessment 2007-2008

    International Nuclear Information System (INIS)

    2010-01-01

    This report presents the results of the analysis of 'patient' dosimetric data which radiology and nuclear medicine establishments must supply every year to the IRSN (the French Radioprotection and Nuclear Safety Institute) according to a decree related to diagnosis reference levels in radiology and nuclear medicine. The analysed dosimetric data concern assessments performed during 2007 and 2008. For the different concerned practices (radiology, scanography, nuclear medicine), the report proposes a presentation and a discussion of global data, and then a presentation of data either for different types of examination on adults and on children, or for the different parts of the body

  8. Siting the nation's first high-level nuclear waste repository: Social impacts for Utah

    International Nuclear Information System (INIS)

    Olshansky, S.J.

    1986-01-01

    The siting of a high-level nuclear waste repository in the United States has been an issue of great controversy, particulary for the states under consideration. In addition to concerns expressed about the geological stability of the proposed sites, numerous social issues have been raised by the general public--most of which have been addressed by the draft environmental impact statements. Among the social impacts raised by the Department of Engery and the general public, those receiving the greatest attention were the potential influence of the repository on local economics, tourism, and the health status of the local residents. The major issues of interest in the present study include 1) the effects of respondent knowledge of nuclear waste disposal issues on opinions of health effects and tourism, particularly as they are affected by visitation patterns, and 2) the effects of occupation and education (in particular) on knowledge of nuclear waste disposal issues and opinions on technical and non-technical aspects of siting the repository. Preliminary results indicate that only about 40 percent of the respondents have visited the national parks in southeastern Utah, but over 70 percent feel they are informed about the issues associated with siting the repository. Over 60 percent of the respondents were very concerned about the possible negative effect the repository could have on jobs, tourism, health effects, and environmental quality. Cross-tabulations indicate that the respondents self rating on knowledge of nuclear disposal issues has a statistically significant influence on responses to socioeconomic issues, yet the same self rating scale is significantly influenced by the frequency with which respondents have visited the national parks in southeastern Utah

  9. Level of occupational exposure during daily work in a Nuclear Medicine Department

    Energy Technology Data Exchange (ETDEWEB)

    Schwarcke, Marcelo, E-mail: mschwarcke@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Dept. de Fisica e Matematica; Ferreira, Nadya [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Nuclear; Cardoso, Domingos [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Workers of the Nuclear Medicine Department have a very complex geometric exposition. The source of irradiation is not collimated and irradiated for all direction, the interaction with many structural tissue is inside the body before could be detected outside. The professional who works in a Nuclear Medicine Department is exposed to this condition and different energies. This work proposes a good approach to estimate the mensal dose level according to the dose rate during their daily routine. To measure the dose rate, a Babyline 81 ionization chamber was used, and the most frequent exams using {sup 99m}Tc were chosen. A previous study was conducted to determine the most frequent exams made in the Nuclear Medicine Department at the Central Army Hospital in Rio de Janeiro, and previous environment monitoring determine the places with higher exposure that could interfere in the measurement of this paper. The Renal scintigraphy with diethylenetriaminepentaacetic acid (DTPA) had an average dose rate of (2.50{+-}0.25) {mu}Sv/h; for the Renal scintigraphy with dimercaptosuccinic acid (DMSA), it was of (1.20{+-}0.25) {mu}Sv/h; for Bone scintigraphy using two different protocols, it was (2.63{+-}0.30) {mu}Sv/h and (3.09{+-}0.30) {mu}Sv/h. Exposition during elution, dose preparing and clinical procedure was considered a critical moment in the daily routine of the employee. The dose rate obtained in this study demonstrated that the professional cannot exceed the public dose limit in one day of his work routine. Therefore, for the Radioprotection Department, this is a good approach to make a radioprotection plan in the Nuclear Medicine Department. (author)

  10. Absorbed dose at subcellular level by Monte Carlo simulation for a {sup 99m}Tc-peptide with nuclear internalization

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E. L.; Ferro F, G. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Santos C, C. L., E-mail: leticia.rojas@inin.gob.m [Universidad Autonoma del Estado de Mexico, Paseo Tollocan esquina Paseo Colon s/n, Toluca 50120, Estado de Mexico (Mexico)

    2010-10-15

    The utility of radiolabeled peptides for the early and specific diagnosis of cancer is being investigated around the world. Recent investigations have demonstrated the specificity of {sup 99m}Tc-bombesin conjugates to target breast and prostate cancer cells. The novel idea of adding the Tat (49-57) peptide to the radiopharmaceutical in order to penetrate the cell nucleus is a new proposal for therapy at cellular level. {sup 99m}Tc radionuclide produces Auger energy of 0.9 keV/decay and internal conversion electron energy of 15.4 keV/decay, which represent 11.4% of the total {sup 99m}Tc energy released per decay. It is expected that the dose delivered at specific microscopic levels in cancer cells induce a therapeutic effect. The aim of this research was to assess in vitro internalization kinetics in breast and prostate cancer cells of {sup 99m}Tc-Tat(49-57)-bombesin and to evaluate the radiation absorbed dose at subcellular level simulating the electron transport. The pen main program from the 2006 version of the Penelope code was used to simulate and calculate the absorbed dose by Auger and internal conversion electron contribution in the membrane, cytoplasm and nucleus of Pc-3 prostate cancer and MCF7 and MDA human breast cancer cell lines. Nuclear data were obtained from the 2002 BNM-LNHB {sup 99m}Tc decay scheme. The spatial distribution of the absorbed doses to the membrane, cytoplasm and nucleus were calculated using a geometric model built from real images of cancer cells. The elemental cell composition was taken from the literature. The biokinetic data were obtained evaluating total disintegrations in each subcellular compartment by integration of the time-activity curves acquired from experimental data. Results showed that 61, 63 and 46% of total disintegrations per cell-bound {sup 99m}Tc-Tat-Bn activity unit occurred in the nucleus of Pc-3, MCF7 and MDA-MB231 respectively. {sup 99m}Tc--Tat-Bn absorbed doses were 1.78, 5.76 and 2.59 Gy/Bq in the nucleus of

  11. Neutron-capture gamma-ray study of levels in 135Ba and description of nuclear levels in the interacting-boson-fermion model

    International Nuclear Information System (INIS)

    Chrien, R.E.; Koene, B.K.S.; Stelts, M.L.; Meyer, R.A.; Brant, S.; Paar, V.; Lopac, V.

    1993-01-01

    We have performed neutron-capture gamma-ray studies on natural and enriched targets of 134 Ba in order to investigate the nuclear levels of 135 Ba. The low-energy level spectra were compared with the calculations using the interacting-boson-fermion model (IBFM) and the cluster-vibration model. The level densities up to 5 MeV that are calculated within the IBFM are in accordance with the constant temperature Fermi gas model. From the spin distribution we have determined the corresponding spin cutoff parameter σ and compared it to the prediction from nuclear systematics

  12. Research on magnetohydrodynamic turbulent behavior. Development of the turbulence model using large eddy simulation. FY15 report of the JNC cooperative research scheme on the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Tanahashi, Takahiko; Miyoshi, Ichiro; Ara, Kuniaki; Ohira, Hiroaki

    2004-08-01

    Investigation of magnetohydrodynamic (MHD) turbulent model with Large Eddy Simulation (LES) method was started in FY15 to evaluate MHD turbulent behavior on the conditions of high Reynolds numbers and high magnetic Reynolds numbers. In FY15, the proposed Subgrid Scale (SGS) model for magnetic fields generated by direct current was formulated with GSMAC-FEM (Generalized Simplified Marker and Cell method for Finite Element Method) and the characteristic behavior of MHD turbulence studied theoretically. A Direct Numerical Simulation (DNS) method was also developed to verify the theoretical study and construct and advanced SGS model. The last purpose of this study is to analyze the realistic Electromagnetic Pump. In order to understand basic concept, analyses of small-scale Electromagnetic Pump was started with A-φ method. The following results were obtained from these studies: (1) Homogeneous turbulent flows in a conducting fluid which were exposed to uniform magnetic fields were examined through the Direct Numerical Simulation and the characteristics of energy distribution were shown in the MHD turbulence at low magnetic Reynolds numbers. (2) For the analysis of the realistic Electromagnetic Pump, the parallel scheme based on GSMAC-FEM was constructed. Effectiveness of the scheme for large-scale calculation was shown through the benchmark problem, three dimensional cavity flow. (3) A new Balancing Tensor Diffusivity (BTD) formulation for the magnetic fields was proposed in this study and the proposed SGS model in previous study was formulated with GSMAC-FEM. The FEM scheme for MHD turbulence at high magnetic Reynolds number was verified through homogeneous MHD turbulence. (4) An A-φ method formulated with GSMAC-FEM was applied to the analysis of small-scale Electromagnetic pump. The basic concepts for the analysis with B method were obtained through the results. (author)

  13. Public Acceptance of Low-Level Waste Disposal Critical to the Nuclear Renaissance

    International Nuclear Information System (INIS)

    Sonny Goldston, W.T.

    2009-01-01

    The disposal of various Low-Level Waste (LLW) forms projected to result from the operation of a pilot or large scale Advanced Fuel Cycle Initiative Programs' (formally known as Global Nuclear Energy Partnership (GNEP)) reprocessing and vitrification plants requires the DOE LLW program and regulatory structure to be utilized in its present form due to the limited availability of Nuclear Regulatory Commission licensed commercial LLW disposal facilities to handle wastes with radionuclide concentrations that are greater than Nuclear Regulatory Commission (NRC) Class A limits. This paper will describe the LLW forms and the regulatory structures and facilities available to dispose of this waste. Then the paper discusses the necessity of an excellent public involvement program to ensure the success of an effective technical solution. All of the decisions associated with the management of these wastes are of interest to the public and successful program implementation would be impossible without including the public up-front in the program formulation. Serious problems can result if program decisions are made without public involvement, and if the public is informed after key decisions are made. This paper will describe the regulatory and public involvement program and their effects on the decisions concerning the disposal of Low-Level Radioactive Waste (LLW) at the Savannah River Site (SRS). An extensive public communications effort resulted in endorsement of changes in disposal practices by the SRS Citizens Advisory Board that was critical to the success of the program. A recommendation will be made to install a public involvement program that is similar to the SRS Citizens Advisory Board in order to ensure the success of the AFCI programs in view of the limited availability to handle the wastes from the program and the public acceptance of change that will be required. (authors)

  14. Integrated Level 3 risk assessment for the LaSalle Unit 2 nuclear power plant

    International Nuclear Information System (INIS)

    Payne, A.C. Jr.; Brown, T.D.; Miller, L.A.

    1991-01-01

    An integrated Level 3 probabilistic risk assessment (PRA) was performed on the LaSalle County Station nuclear power plant using state-of-the-art PRA analysis techniques. The objective of this study was to provide an estimate of the risk to the offsite population during full power operation of the plant and to include a characterization of the uncertainties in the calculated risk values. Uncertainties were included in the accident frequency analysis, accident progression analysis, and the source term analysis. Only weather uncertainties were included in the consequence analysis. In this paper selected results from the accident frequency, accident progression, source term, consequence, and integrated risk analyses are discussed and the methods used to perform a fully integrated Level 3 PRA are examined. LaSalle County Station is a two-unit nuclear power plant located 55 miles southwest of Chicago, Illinois. Each unit utilizes a Mark 2 containment to house a General Electric 3323 MWt BWR-5 reactor. This PRA, which was performed on Unit 2, included internal as well as external events. External events that were propagated through the risk analysis included earthquakes, fires, and floods. The internal event accident scenarios included transients, transient-induced LOCAs (inadvertently stuck open relief valves), anticipated transients without scram, and loss of coolant accidents

  15. Fair rules for siting a high-level nuclear waste repository

    International Nuclear Information System (INIS)

    Easterling, D.

    1992-01-01

    Geologic repositories are designed to resolve the ever-growing problem of high-level nuclear waste, but these facilities invite intense local opposition due to the perceived severity of the risks and the possibility of stigma effects. This analysis examines whether the perceived fairness of the siting process affects local residents' support for hosting a repository. In particular, a survey of 1,001 Nevada residents is used to test the hypothesis that an individual's willingness to accept a local repository will increase if he or she is convinced that this is the safest disposal option available. A logistic analysis indicates that beliefs regarding relative suitability have an independent effect on the acceptability of a local repository (i.e., Yucca Mountain). The article then considers the question of how to implement an optimizing strategy for siting facilities, comparing an idealized strategy against the original Nuclear Waste Policy Act (NWPA) of 1982 and the Amendments Act of 1987. Although choosing the safest site seems as if it could enhance public acceptance of the repository program, there is currently little prospect of identifying the best option to the high-level waste problem and, as a results, little chance of gaining the public support that is necessary to promote a successful siting outcome. 81 refs., 1 fig., 5 tabs

  16. Evaluation of cytogenetic damage in nuclear medicine personnel occupationally exposed to low-level ionising radiation

    International Nuclear Information System (INIS)

    Garaj-Vrhovac, V.; Kopjar, N.; Poropat, M.

    2005-01-01

    Despite intensive research over the last few decades, there still remains considerable uncertainty as to the genetic impact of ionising radiation on human populations, particularly at low levels. The aim of this study was to provide data on genetic hazards associated with occupational exposure to low doses of ionising radiation in nuclear medicine departments. The assessment of DNA damage in peripheral blood lymphocytes of medical staff was performed using the chromosome aberration (CA) test. Exposed subjects showed significantly higher frequencies of CA than controls. There were significant inter-individual differences in DNA damage within the exposed population, indicating differences in genome sensitivity. Age and gender were not confounding factors, while smoking enhanced the levels of DNA damage only in control subjects. The present study suggests that chronic exposure to low doses of ionising radiation in nuclear medicine departments causes genotoxic damage. Therefore, to avoid potential genotoxic effects, the exposed medical personnel should minimise radiation exposure wherever possible. Our results also point to the significance of biological indicators providing information about the actual risk to the radiation exposed individuals.(author)

  17. Glass: a candidate engineered material for management of high level nuclear waste

    International Nuclear Information System (INIS)

    Mishra, R.K.; Kaushik, C.P.

    2011-01-01

    While the commercial importance of glass is generally recognized, a few people are aware of extremely wide range of glass formulations that can be made and of the versatility of this engineered material. Some of the recent developments in the field of glass leading to various technological applications include glass fiber reinforcement of cement to give new building materials, substrates for microelectronics circuitry in form of semiconducting glasses, nuclear waste immobilization and specific medical applications. The present paper covers fundamental understanding of glass structure and its application for immobilization of high level radioactive liquid waste. High level radioactive liquid waste (HLW) arising during reprocessing of spent fuel are immobilized in sodium borosilicate glass matrix developed indigenously. Glass compositions are modified according to the composition of HLW to meet the criteria of desirable properties in terms. These glass matrices have been characterized for different properties like homogeneity, chemical durability, thermal stability and radiation stability. (author)

  18. Measurements of the ionising radiation level at a nuclear medicine facility performing PET/CT examinations

    International Nuclear Information System (INIS)

    Tulik, P.; Kowalska, M.; Golnik, N.; Budzynska, A.; Dziuk, M.

    2017-01-01

    This paper presents the results of radiation level measurements at workplaces in a nuclear medicine facility performing PET/ CT examinations. This study meticulously determines the staff radiation exposure in a PET/CT facility by tracking the path of patient movement. The measurements of the instantaneous radiation exposure were performed using an electronic radiometer with a proportional counter that was equipped with the option of recording the results on line. The measurements allowed for visualisation of the staff's instantaneous exposure caused by a patient walking through the department after the administration of "1"8F-FDG. An estimation of low doses associated with each working step and the exposure during a routine day in the department was possible. The measurements were completed by determining the average radiation level using highly sensitive thermoluminescent detectors. (authors)

  19. Effect of different level density prescriptions on the calculated neutron nuclear reaction cross sections

    International Nuclear Information System (INIS)

    Garg, S.B.

    1991-01-01

    A detailed investigation is carried out to determine the effect of different level density prescriptions on the computed neutron nuclear data of Ni-58 in the energy range 5-25 MeV. Calculations are performed in the framework of the multistep Hauser-Feshbach statistical theory including the Kalbach exciton model and Brink-Axel giant dipole resonance model for radiative capture. Level density prescriptions considered in this investigation are based on the original Gilbert-Cameron, improved Gilbert-Cameron, backshifted Fermi-gas and the Ignatyuk, et al. approaches. The effect of these prescriptions is discussed, with special reference to (n,p), (n,2n), (n,alpha) and total particle-production cross sections. (author). 17 refs, 8 figs

  20. Determination of the lowest critical power levels of the Dalat Nuclear Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Huy, Ngo Quang [Centre for Nuclear Technique Application, Ho Chi Minh City (Viet Nam); Thong, Ha Van; Long, Vu Hai; Binh, Do Quang; Nghiem, Huynh Ton; Tuan, Nguyen Minh; Vien, Luong Ba; Vinh, Le Vinh [Nuclear Research Inst., Da Lat (Viet Nam)

    1994-10-01

    This paper presents the experimental methods for determining critical states of the Dalat Nuclear Research Reactor containing an extraneous neutron source induced by gamma ray reactions on beryllium in the reactor. The lowest critical power levels are measured at various moments after the reactor is shut down following 100 hours of its continuous operation. Th power levels vary from (0.5-1.2) x 10{sup -4} of P{sub n}, i.e. (25-60)W to (1.1-1.6) x 10{sup -5} of P{sub n}, i.e. (5.5-8)W at corresponding times of 4 days to 13 days after the reactor is shut down. However the critical power must be chosen greater than 500 W to sustain the steady criticality of the reactor for a long time. (author). 3 refs. 4 figs. 1 tab.

  1. Screening level dose assessment of aquatic biota downstream of the Marcoule nuclear complex in southern France.

    Science.gov (United States)

    St-Pierre, S; Chambers, D B; Lowe, L M; Bontoux, J G

    1999-09-01

    Aquatic biota in the Rhone River downstream of the Marcoule nuclear complex in France are exposed to natural sources of radiation and to radioactivity released from the Marcoule complex. A simple conservative screening level model was used to estimate the range of concentrations in aquatic media (water, sediments, and aquatic organisms) of both artificial and natural radionuclides and the consequent absorbed (whole body) dose rates for aquatic organisms. Five categories of aquatic organisms were studied, namely, submerged aquatic plants (phanerogam), non-bottom-feeding fish, bottom-feeding fish, mollusca, and fish-eating birds. The analysis was based on the radionuclide concentrations reported in four consecutive annual radioecological monitoring reports published by French agencies with nuclear regulatory responsibilities. The results of this assessment were used to determine, qualitatively, the magnitude of any potential health impacts on each of the five categories of aquatic organisms studied. The range of dose rate estimates ranged over three orders of magnitude, with maximum dose rates estimated to be in the order of 1 to 10 microGy h(-1). These maximum dose rates are a factor 40 or more below the international guideline intended to ensure the protection of aquatic populations (about 400 microGy h(-1)), and a factor ten or more below the level which may trigger the need for a more detailed evaluation of potential ecological consequences to the exposed populations (about 100 microGy h(-1)). As a result, chronic levels of radioactivity, artificial and natural, measured in aquatic media downstream of Marcoule are unlikely to result in adverse health impacts on the categories and species of aquatic organisms studied. Thus, based on the screening level analysis discussed in this paper, a more detailed evaluation of the dose rates does not appear to be warranted.

  2. Design of an optimal automatic regulator for regulating the power levels of a nuclear reactor in a wind power range

    International Nuclear Information System (INIS)

    Noori Khajavi, M.; Menhaj, M.B.; Ghofrani, M.B.

    2000-01-01

    Nuclear power reactors are, in nature nonlinear and time varying. These characteristics must be considered, if large power variations occur in their working regime. In this paper a robust optimal self-tuning regulator for regulating the power of a nuclear reactor has been designed and simulated. The proposed controller is capable of regulating power levels in a wide power range (10% to 100% power levels). The controller achieves a fast and good transient response. The simulation results show that the proposed controller outperforms the fixed optimal control recently cited in the literature for nuclear power plants

  3. Role of proper response schemes, legislation and regional co-operation in combating illicit trafficking of nuclear materials in developing countries

    International Nuclear Information System (INIS)

    Sterzov, A.

    2003-01-01

    Bulgaria's geographical location - between Europe, the former Soviet Union, and the Middle East - exposes it to much illegal trafficking: of people, arms, drugs, etc. The trafficking of nuclear and radioactive materials in Bulgaria can be divided in two main parts - internal and transit. Internal trafficking consists of stolen radioactive sources such as counters and densitometers, irradiation devices, tools for removing static electricity, and smoke detectors, which mainly contain the isotopes 137 Cs, 60 Co, 192 Ir, 226 Ra and 241 Am. The external trafficking of illicit nuclear materials is connected with transfer of raw materials and expensive metals from the former Soviet Union to countries in Western Europe and the Middle East, including aluminium, osmium, caesium, scandium, rare earth elements, red mercury, plutonium and enriched uranium. Detecting internal and external trafficking poses serious problems for the Bulgarian authorities, in terms of equipment and qualified personnel at the borders and inside the country. Developing countries need protocols for detecting and responding to illicit trafficking of nuclear materials, which is a new threat that requires rapid implementation of comprehensive measures and efforts, novel approaches, coordination of services and institutions, and even new legislation. The paper describes a three step model for better and more rapid responses for combating illicit nuclear trafficking in Bulgaria.The steps involve developing first response protocols, using nondestructive analytical means to categorize materials on-site, followed by in-depth analysis. It is also important to initiate contacts with neighbouring countries to foster regional collaboration among law enforcement agencies, customs authorities, analytical laboratories, etc., to improve efficiency in combating illicit trafficking of nuclear materials. (author)

  4. Status of nuclear fuel reprocessing, spent fuel storage, and high-level waste disposal. Nuclear Fuel Cycle Committee, California Energy Resources Conservation and Development Commission. Draft report

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    An analysis of the current status of technologies and issues in the major portions of the back-end of the nuclear fuel cycle is presented. The discussion on nuclear fuel reprocessing covers the reprocessing requirement, reprocessing technology assessment, technology for operation of reprocessing plants, and approval of reprocessing plants. The chapter devoted to spent fuel storage covers the spent fuel storge problem, the legislative response, options for maintaining full core discharge capacity, prospective availability of alterntive storage options, and the outlook for California. The existence of a demonstrated, developed high-level waste disposal technology is reviewed. Recommendations for Federal programs on high-level waste disposal are made

  5. Attitudes and opposition in siting a high level nuclear waste repository

    International Nuclear Information System (INIS)

    Sjoeberg, L.; Viklund, M.; Truedsson, J.

    1998-09-01

    In Sweden, the Swedish Nuclear Fuel and Waste Management Company (SKB) handles all issues concerning nuclear waste, including the siting process, in which the final outcome is intended to be a repository for high level nuclear waste placed deep down in bedrock. The main objective of the siting process is to find a host community fulfilling two important conditions: the safety demands have been met and agreements with the municipality can be accomplished. Only in such municipalities, so-called feasibility studies will be conducted. After conducting general studies in the whole country, SKB, in October 1992, sent letters with information about the intended feasibility studies to all Swedish municipalities. As a result, feasibility studies are or have been considered - and in some cases also been conducted - in eleven Swedish municipalities up until 1998. These are the municipalities where the attitudes and opposition towards a feasibility study, and possibly a final repository, are studied. The discussion can be divided into three main parts: Management of the siting process; Inherent 'chaotic' processes and/or factors and risk perception. It is argued that two important problems could have been avoided at least partly: The citizens in many municipalities were uncertain of the relationship between a feasibility study and a final repository, and in many municipalities the citizens were afraid that the Government could overrule the municipal veto. Because of these fears, a common argument among the opponents of a feasibility study was: 'to be sure of not receiving a final repository, we say no to a feasibility study'. Some inherent factors, more or less prevalent in the municipalities as well as in society in general, may also partly explain the outcome of the siting process. The municipalities in which the debate has been heated, and where public support has been more difficult to reach, share some common characteristics. Esp. in the municipalities in the north of

  6. Attitudes and opposition in siting a high level nuclear waste repository

    Energy Technology Data Exchange (ETDEWEB)

    Sjoeberg, L.; Viklund, M.; Truedsson, J

    1998-09-01

    In Sweden, the Swedish Nuclear Fuel and Waste Management Company (SKB) handles all issues concerning nuclear waste, including the siting process, in which the final outcome is intended to be a repository for high level nuclear waste placed deep down in bedrock. The main objective of the siting process is to find a host community fulfilling two important conditions: the safety demands have been met and agreements with the municipality can be accomplished. Only in such municipalities, so-called feasibility studies will be conducted. After conducting general studies in the whole country, SKB, in October 1992, sent letters with information about the intended feasibility studies to all Swedish municipalities. As a result, feasibility studies are or have been considered - and in some cases also been conducted - in eleven Swedish municipalities up until 1998. These are the municipalities where the attitudes and opposition towards a feasibility study, and possibly a final repository, are studied. The discussion can be divided into three main parts: Management of the siting process; Inherent `chaotic` processes and/or factors and risk perception. It is argued that two important problems could have been avoided at least partly: The citizens in many municipalities were uncertain of the relationship between a feasibility study and a final repository, and in many municipalities the citizens were afraid that the Government could overrule the municipal veto. Because of these fears, a common argument among the opponents of a feasibility study was: `to be sure of not receiving a final repository, we say no to a feasibility study`. Some inherent factors, more or less prevalent in the municipalities as well as in society in general, may also partly explain the outcome of the siting process. The municipalities in which the debate has been heated, and where public support has been more difficult to reach, share some common characteristics. Esp. in the municipalities in the north of

  7. Analysis of opinion about nuclear energy and sustainability in a graduate level population; Analisis de opinion sobre la energia nuclear y sustentabilidad en una poblacion de nivel superior

    Energy Technology Data Exchange (ETDEWEB)

    Meza L, C.D.; Arredondo S, C. [IPN, ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: angie2esa@hotmail.com

    2007-07-01

    The Mexican society has a modest knowledge of the nuclear energy, even at the participant students of superior education level in this survey is finds a scarce compression with regard to their obtaining, use and manage. As a result of the lack of interest of the same society and at the problems that know each other like they are: the pollutants that it produces those nuclear waste and the possible use or warlike end, a fear is believed about this energy type. In the Superior School of Physics and Mathematics there is the possibility to make studies so much at master degree level in the one fear of the nuclear energy and the applications of the same one in peaceful uses. However, particularly the studies at master level seem to be immersed in a crisis that requires of different supports to be resolved. For all it previous was thought in carrying out a survey inside a student population with superior level to know the opinion and the knowledge on the nuclear energy in Mexico. In this work the results of the survey are analyzed with the purpose of to determine which is the knowledge of the community mentioned regarding the other energy types, the impact that they have these in the environment, the sustenance of the same ones and in particular on knowledge about the nuclear energy considering the aspects before mentioned. With base had said analysis settles down that the interviewed community knows very little about the nuclear energy but they show interest to study and to obtain bigger information about the same one, for what is very important to diffuse but and better information on the nuclear energy to the population's strata, because it is of supposing that the rest of the population has erroneous information on the nuclear energy. In particular for the community of the Superior School of Physics and Mathematics the diffusion of all the benefits of the peaceful applications of the nuclear energy, including the capacity to generate enormous quantities and

  8. Comparison of p53 levels in lymphocytes and in blood plasma of nuclear power plant workers

    International Nuclear Information System (INIS)

    Roessner, Pavel; Chvatalova, Irena; Schmuczerova, Jana; Milcova, Alena; Roessner, Pavel; Sram, Radim J.

    2004-01-01

    p53 levels were assessed in lymphocytes and in blood plasma of workers from two Czech nuclear power plants (NPP): 114 subjects working in Temelin and 108 subjects working in Dukovany. Ionizing radiation (IR) exposure data were available for 64 and 59 subjects working in the monitored zones from the NPP in Temelin and Dukovany, respectively. The short-term doses of IR for these subjects were 0.01 and 0.12 mSv, and the long-term doses were 0.46 and 5.68 mSv, in the Temelin and Dukovany NPP, respectively. As a control group, 46 subjects living in Ceske Budejovice, a city nearby the Temelin NPP, were analyzed. The concentration of p53 in lymphocytes was significantly higher in workers from the monitored zone in the Dukovany NPP (median value 6.4 pg/μg protein, P < 0.001) than in workers from the Temelin NPP (3.2 pg/μg) as well as in the control group (3.5 pg/μg). In contrast, plasma levels of p53 were comparable in the control group (median value 116 pg/ml plasma) and workers from the monitored zone of Dukovany NPP (102 pg/ml), but lower in workers from Temelin NPP (5 pg/ml). Other factors affecting p53 levels were studied. Smoking resulted in increased p53 lymphocyte levels. The effect of polymorphisms in metabolic and DNA repair genes on p53 levels was analyzed. The correlation was found between p53 levels in lymphocytes and p53 codon 72 polymorphism in subjects working in NPPs, but not in the control group. The results of measurement p53 levels in lymphocytes suggest that this biomarker could reflect the short-term as well as long-term effects of low doses IR. Its impact on human health should be further explored

  9. Research on the improvement of nuclear safety -Improvement of level 1 PSA computer code package-

    International Nuclear Information System (INIS)

    Park, Chang Kyoo; Kim, Tae Woon; Kim, Kil Yoo; Han, Sang Hoon; Jung, Won Dae; Jang, Seung Chul; Yang, Joon Un; Choi, Yung; Sung, Tae Yong; Son, Yung Suk; Park, Won Suk; Jung, Kwang Sub; Kang Dae Il; Park, Jin Heui; Hwang, Mi Jung; Hah, Jae Joo

    1995-07-01

    This year is the third year of the Government-sponsored mid- and long-term nuclear power technology development project. The scope of this sub project titled on 'The improvement of level-1 PSA computer codes' is divided into three main activities : (1) Methodology development on the underdeveloped fields such as risk assessment technology for plant shutdown and low power situations, (2) Computer code package development for level-1 PSA, (3) Applications of new technologies to reactor safety assessment. At first, in this area of shutdown risk assessment technology development, plant outage experiences of domestic plants are reviewed and plant operating states (POS) are decided. A sample core damage frequency is estimated for over draining event in RCS low water inventory i.e. mid-loop operation. Human reliability analysis and thermal hydraulic support analysis are identified to be needed to reduce uncertainty. Two design improvement alternatives are evaluated using PSA technique for mid-loop operation situation: one is use of containment spray system as backup of shutdown cooling system and the other is installation of two independent level indication system. Procedure change is identified more preferable option to hardware modification in the core damage frequency point of view. Next, level-1 PSA code KIRAP is converted to PC-windows environment. For the improvement of efficiency in performing PSA, the fast cutest generation algorithm and an analytical technique for handling logical loop in fault tree modeling are developed. 48 figs, 15 tabs, 59 refs. (Author)

  10. Improving the description of collective effects within the combinatorial model of nuclear level densities

    International Nuclear Information System (INIS)

    Hilaire, S.; Girod, M.; Goriely, S.

    2011-01-01

    The combinatorial model of nuclear level densities has now reached a level of accuracy comparable to that of the best global analytical expressions without suffering from the limits imposed by the statistical hypothesis on which the latter expressions rely. In particular, it provides naturally, non Gaussian spin distribution as well as non equipartition of parities which are known to have a significant impact on cross section predictions at low energies. Our first global model developed in Ref. 1 suffered from deficiencies, in particular in the way the collective effects - both vibrational and rotational - were treated. We have recently improved this treatment using simultaneously the single particle levels and collective properties predicted by a newly derived Gogny interaction, therefore enabling a microscopic description of energy-dependent shell, pairing and deformation effects. In addition, for deformed nuclei, the transition to sphericity is coherently taken into account on the basis of a temperature-dependent Hartree-Fock calculation which provides at each temperature the structure properties needed to build the level densities. This new method is described and shown to give promising preliminary results with respect to available experimental data. (authors)

  11. Research on the improvement of nuclear safety -Improvement of level 1 PSA computer code package-

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chang Kyoo; Kim, Tae Woon; Kim, Kil Yoo; Han, Sang Hoon; Jung, Won Dae; Jang, Seung Chul; Yang, Joon Un; Choi, Yung; Sung, Tae Yong; Son, Yung Suk; Park, Won Suk; Jung, Kwang Sub; Kang Dae Il; Park, Jin Heui; Hwang, Mi Jung; Hah, Jae Joo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-07-01

    This year is the third year of the Government-sponsored mid- and long-term nuclear power technology development project. The scope of this sub project titled on `The improvement of level-1 PSA computer codes` is divided into three main activities : (1) Methodology development on the underdeveloped fields such as risk assessment technology for plant shutdown and low power situations, (2) Computer code package development for level-1 PSA, (3) Applications of new technologies to reactor safety assessment. At first, in this area of shutdown risk assessment technology development, plant outage experiences of domestic plants are reviewed and plant operating states (POS) are decided. A sample core damage frequency is estimated for over draining event in RCS low water inventory i.e. mid-loop operation. Human reliability analysis and thermal hydraulic support analysis are identified to be needed to reduce uncertainty. Two design improvement alternatives are evaluated using PSA technique for mid-loop operation situation: one is use of containment spray system as backup of shutdown cooling system and the other is installation of two independent level indication system. Procedure change is identified more preferable option to hardware modification in the core damage frequency point of view. Next, level-1 PSA code KIRAP is converted to PC-windows environment. For the improvement of efficiency in performing PSA, the fast cutest generation algorithm and an analytical technique for handling logical loop in fault tree modeling are developed. 48 figs, 15 tabs, 59 refs. (Author).

  12. West Valley high-level nuclear waste glass development: a statistically designed mixture study

    Energy Technology Data Exchange (ETDEWEB)

    Chick, L.A.; Bowen, W.M.; Lokken, R.O.; Wald, J.W.; Bunnell, L.R.; Strachan, D.M.

    1984-10-01

    The first full-scale conversion of high-level commercial nuclear wastes to glass in the United States will be conducted at West Valley, New York, by West Valley Nuclear Services Company, Inc. (WVNS), for the US Department of Energy. Pacific Northwest Laboratory (PNL) is supporting WVNS in the design of the glass-making process and the chemical formulation of the glass. This report describes the statistically designed study performed by PNL to develop the glass composition recommended for use at West Valley. The recommended glass contains 28 wt% waste, as limited by process requirements. The waste loading and the silica content (45 wt%) are similar to those in previously developed waste glasses; however, the new formulation contains more calcium and less boron. A series of tests verified that the increased calcium results in improved chemical durability and does not adversely affect the other modeled properties. The optimization study assessed the effects of seven oxide components on glass properties. Over 100 melts combining the seven components into a wide variety of statistically chosen compositions were tested. Viscosity, electrical conductivity, thermal expansion, crystallinity, and chemical durability were measured and empirically modeled as a function of the glass composition. The mathematical models were then used to predict the optimum formulation. This glass was tested and adjusted to arrive at the final composition recommended for use at West Valley. 56 references, 49 figures, 18 tables.

  13. Development of Soil Derived Concentration Guidance Levels for Decommissioning at Overseas Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Wook; Yoon, Suk Bon; Kim, Jeongju [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    In Korea, the criteria are expected to be given in terms of dose as in US and Spain. However, since dose cannot be measured, corresponding measurable concentration limits, so-called Derived Concentration Guidance Levels (DCGLs), should be developed for each radionuclide which is expected to be present in the site. Also, as they serve as a goal of decommissioning and direct dismantling and decontamination methods applicable to the site, DCGLs should be developed in the early phase of decommissioning. This paper describes how each overseas nuclear power plant developed its site-specific Soil DCGLs: what kind of post closure use of the site (scenario) was assumed and how the site-specific Soil DCGLs were calculated based on the scenario assumed for each plant. Through this, it is intended to derive lessons learned which will be instructive for future decommissioning of domestic nuclear power plants including Kori Unit 1. It is very important to have as good under-standing as possible of characteristics of the site by collection of relevant information and data in order to apply a scenario which is most foreseeable and plausible for a site to be decommissioned and to provide site-specific inputs to the calculation of the Soil DCGLs. These efforts will help to have not-overly conservative values for the Soil DCGLs, thus thereby reducing the costs and time needed for performing the decommissioning.

  14. Survey and evaluation of handling and disposing of solid low-level nuclear fuel cycle wastes

    International Nuclear Information System (INIS)

    Mullarkey, T.B.; Jentz, T.L.; Connelly, J.M.; Kane, J.P.

    1976-10-01

    The report identifies the types and quantities of low-level solid radwaste for each portion of the nuclear fuel cycle, based on operating experiences at existing sites and design information for future installations. These facts are used to evaluate reference 1000 MWe reactor plants in terms of solid radwaste generation. The effect of waste volumes on disposal methods and land usage has also been determined, based on projections of nuclear power growth through the year 2000. The relative advantages of volume reduction alternatives are included. Major conclusions are drawn concerning available land burial space, light water reactors and fuel fabrication and reprocessing facilities. Study was conducted under the direction of an industry task force and the National Environmental Studies Project, a technical program of the Atomic Industrial Forum. Data was obtained from questionnaires sent to 8 fuel fabrication facilities, 39 reactor sites and 6 commercial waste disposal sites. Additional data were gathered from interviews with architect engineering firms, site visits, contacts with regulatory agencies and published literature

  15. Anticipated Degradation Modes of Metallic Engineered Barriers for High-Level Nuclear Waste Repositories

    Science.gov (United States)

    Rodríguez, Martín A.

    2014-03-01

    Metallic engineered barriers must provide a period of absolute containment to high-level radioactive waste in geological repositories. Candidate materials include copper alloys, carbon steels, stainless steels, nickel alloys, and titanium alloys. The national programs of nuclear waste management have to identify and assess the anticipated degradation modes of the selected materials in the corresponding repository environment, which evolves in time. Commonly assessed degradation modes include general corrosion, localized corrosion, stress-corrosion cracking, hydrogen-assisted cracking, and microbiologically influenced corrosion. Laboratory testing and modeling in metallurgical and environmental conditions of similar and higher aggressiveness than those expected in service conditions are used to evaluate the corrosion resistance of the materials. This review focuses on the anticipated degradation modes of the selected or reference materials as corrosion-resistant barriers in nuclear repositories. These degradation modes depend not only on the selected alloy but also on the near-field environment. The evolution of the near-field environment varies for saturated and unsaturated repositories considering backfilled and unbackfilled conditions. In saturated repositories, localized corrosion and stress-corrosion cracking may occur in the initial aerobic stage, while general corrosion and hydrogen-assisted cracking are the main degradation modes in the anaerobic stage. Unsaturated repositories would provide an oxidizing environment during the entire repository lifetime. Microbiologically influenced corrosion may be avoided or minimized by selecting an appropriate backfill material. Radiation effects are negligible provided that a thick-walled container or an inner shielding container is used.

  16. Investigation of the tritium level in the environment of the Karlsruhe Nuclear Research Center

    International Nuclear Information System (INIS)

    Koenig, L.A.; Winter, M.; Schueler, H.; Tachlinski, W.

    1976-06-01

    Under an IAEA sponsored measurement program the tritium level is investigated in the immediate and more distant environment of the Karlsruhe Nuclear Research Center. The tritium concentration in precipitations, surface, ground and drinking water is measured within a long-term program. In addition, relationships existing between the tritium concentration of plants and the concentrations of ground water, precipitation, soil and air humidities are investigated at three points in special series of measurement. A summary report is presented on recent measured results. According to these results, the annual mean values for precipitations and surface water tend to rise. In 1975 the annual mean values amounted to 0.89 nCi/l of tritium concentration in precipitations in the more distant environment of the Nuclear Research Center and to 0.68 nCi/l in the Rhine river. In plants tritium concentrations were observed which correspond to that measured in the humidity of the air. The radiation exposure of people living in large towns is calculated to be about 50 μrem/a in the region monitored, due to the presence of tritium in the drinking water. A little group of the population takes up as much as 110 μrem/a. (orig.) [de

  17. Conceptualization of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff

    International Nuclear Information System (INIS)

    Parsons, A.M.; Olague, N.E.; Gallegos, D.P.

    1991-01-01

    Under the sponsorship of the US Nuclear Regulatory Commission (NRC), Sandia National Laboratories (SNL) is developing a performance assessment methodology for the analysis of long-term disposal and isolation of high-level nuclear wastes (HLW) in alternative geologic media. As part of this exercise, SNL created a conceptualization of ground-water flow and radionuclide transport in the far field of a hypothetical HLW repository site located in unsaturated, fractured tuff formations. This study provides a foundation for the development of conceptual mathematical, and numerical models to be used in this performance assessment methodology. This conceptualization is site specific in terms of geometry, the regional ground-water flow system, stratigraphy, and structure in that these are based on information from Yucca Mountain located on the Nevada Test Site. However, in terms of processes in unsaturated, fractured, porous media, the model is generic. This report also provides a review and evaluation of previously proposed conceptual models of unsaturated and saturated flow and solute transport. This report provides a qualitative description of a hypothetical HLW repository site in fractured tuff. However, evaluation of the current knowledge of flow and transport at Yucca Mountain does not yield a single conceptual model. Instead, multiple conceptual models are possible given the existing information

  18. Conceptualization of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, A.M.; Olague, N.E.; Gallegos, D.P. [Sandia National Labs., Albuquerque, NM (USA)

    1991-01-01

    Under the sponsorship of the US Nuclear Regulatory Commission (NRC), Sandia National Laboratories (SNL) is developing a performance assessment methodology for the analysis of long-term disposal and isolation of high-level nuclear wastes (HLW) in alternative geologic media. As part of this exercise, SNL created a conceptualization of ground-water flow and radionuclide transport in the far field of a hypothetical HLW repository site located in unsaturated, fractured tuff formations. This study provides a foundation for the development of conceptual mathematical, and numerical models to be used in this performance assessment methodology. This conceptualization is site specific in terms of geometry, the regional ground-water flow system, stratigraphy, and structure in that these are based on information from Yucca Mountain located on the Nevada Test Site. However, in terms of processes in unsaturated, fractured, porous media, the model is generic. This report also provides a review and evaluation of previously proposed conceptual models of unsaturated and saturated flow and solute transport. This report provides a qualitative description of a hypothetical HLW repository site in fractured tuff. However, evaluation of the current knowledge of flow and transport at Yucca Mountain does not yield a single conceptual model. Instead, multiple conceptual models are possible given the existing information.

  19. Quark-level analogue of nuclear fusion with doubly heavy baryons.

    Science.gov (United States)

    Karliner, Marek; Rosner, Jonathan L

    2017-11-01

    The essence of nuclear fusion is that energy can be released by the rearrangement of nucleons between the initial- and final-state nuclei. The recent discovery of the first doubly charmed baryon , which contains two charm quarks (c) and one up quark (u) and has a mass of about 3,621 megaelectronvolts (MeV) (the mass of the proton is 938 MeV) also revealed a large binding energy of about 130 MeV between the two charm quarks. Here we report that this strong binding enables a quark-rearrangement, exothermic reaction in which two heavy baryons (Λ c ) undergo fusion to produce the doubly charmed baryon and a neutron n (), resulting in an energy release of 12 MeV. This reaction is a quark-level analogue of the deuterium-tritium nuclear fusion reaction (DT → 4 He n). The much larger binding energy (approximately 280 MeV) between two bottom quarks (b) causes the analogous reaction with bottom quarks () to have a much larger energy release of about 138 MeV. We suggest some experimental setups in which the highly exothermic nature of the fusion of two heavy-quark baryons might manifest itself. At present, however, the very short lifetimes of the heavy bottom and charm quarks preclude any practical applications of such reactions.

  20. REGIONAL BINNING FOR CONTINUED STORAGE OF SPENT NUCLEAR FUEL AND HIGH-LEVEL WASTES

    Energy Technology Data Exchange (ETDEWEB)

    W. Lee Poe, Jr

    1998-10-01

    In the Continued Storage Analysis Report (CSAR) (Reference 1), DOE decided to analyze the environmental consequences of continuing to store the commercial spent nuclear fuel (SNF) at 72 commercial nuclear power sites and DOE-owned spent nuclear fuel and high-level waste at five Department of Energy sites by region rather than by individual site. This analysis assumes that three commercial facilities pairs--Salem and Hope Creek, Fitzpatrick and Nine-Mile Point, and Dresden and Moms--share common storage due to their proximity to each other. The five regions selected for this analysis are shown on Figure 1. Regions 1, 2, and 3 are the same as those used by the Nuclear Regulatory Commission in their regulatory oversight of commercial power reactors. NRC Region 4 was subdivided into two regions to more appropriately define the two different climates that exist in NRC Region 4. A single hypothetical site in each region was assumed to store all the SNF and HLW in that region. Such a site does not exist and has no geographic location but is a mathematical construct for analytical purposes. To ensure that the calculated results for the regional analyses reflect appropriate inventory, facility and material degradation, and radionuclide transport, the waste inventories, engineered barriers, and environmental conditions for the hypothetical sites were developed from data for each of the existing sites within the given region. Weighting criteria to account for the amount and types of SNF and HLW at each site were used in the development of the environmental data for the regional site, such that the results of the analyses for the hypothetical site were representative of the sum of the results of each actual site if they had been modeled independently. This report defines the actual site data used in development of this hypothetical site, shows how the individual site data was weighted to develop the regional site, and provides the weighted data used in the CSAR analysis. It is

  1. REGIONAL BINNING FOR CONTINUED STORAGE OF SPENT NUCLEAR FUEL AND HIGH-LEVEL WASTES

    International Nuclear Information System (INIS)

    W. Lee Poe, Jr.

    1998-01-01

    In the Continued Storage Analysis Report (CSAR) (Reference 1), DOE decided to analyze the environmental consequences of continuing to store the commercial spent nuclear fuel (SNF) at 72 commercial nuclear power sites and DOE-owned spent nuclear fuel and high-level waste at five Department of Energy sites by region rather than by individual site. This analysis assumes that three commercial facilities pairs--Salem and Hope Creek, Fitzpatrick and Nine-Mile Point, and Dresden and Moms--share common storage due to their proximity to each other. The five regions selected for this analysis are shown on Figure 1. Regions 1, 2, and 3 are the same as those used by the Nuclear Regulatory Commission in their regulatory oversight of commercial power reactors. NRC Region 4 was subdivided into two regions to more appropriately define the two different climates that exist in NRC Region 4. A single hypothetical site in each region was assumed to store all the SNF and HLW in that region. Such a site does not exist and has no geographic location but is a mathematical construct for analytical purposes. To ensure that the calculated results for the regional analyses reflect appropriate inventory, facility and material degradation, and radionuclide transport, the waste inventories, engineered barriers, and environmental conditions for the hypothetical sites were developed from data for each of the existing sites within the given region. Weighting criteria to account for the amount and types of SNF and HLW at each site were used in the development of the environmental data for the regional site, such that the results of the analyses for the hypothetical site were representative of the sum of the results of each actual site if they had been modeled independently. This report defines the actual site data used in development of this hypothetical site, shows how the individual site data was weighted to develop the regional site, and provides the weighted data used in the CSAR analysis. It is

  2. Applicability of Machine-Learning Enabled LIBS in Post Irradiation Nuclear Forensic Analysis of High Level Nuclear Waste

    International Nuclear Information System (INIS)

    Onkongi, J.; Maina, D.; Angeyo, H. K.

    2017-01-01

    Nuclear Forensics seeks Information to determine; Chemical Composition, Routes of transit, Origin (Provenance) and Intended use. Post Irradiation/Post detonation NF In a post-detonation event could you get clues/signatures from glass debris, minute sample sizes? Nuclear Forensic Technique Should be State-of -the art that is Rapid, Non-invasive, Remote ability and Non-destructive. Laser Induced Breakdown Spectroscopy (LIBS) unlike other Analytic Techniques that require tedious sample preparations such as Dissolution, digestion & matrix removal, which generate additional nuclear wastes that require proper Procedures for handling, storage & ultimate disposal, LIBS overcomes these limitations. Utility of Machine Learning Techniques employed include; Artificial Neural Networks, ANN (Regression/Modelling), Principal component Analysis, PCA (Classification) and Support Vector Machine SVM (Comparative study/Classification Machine Learning coupled with LIBS gives a state of the art analytic method. Utility of the technic in safeguards security and non-proliferation

  3. Formal and informal decision making on water management at the village level: A case study from the Office du Niger irrigation scheme (Mali)

    Science.gov (United States)

    Vandersypen, Klaartje; Keita, Abdoulaye C. T.; Coulibaly, Y.; Raes, D.; Jamin, J.-Y.

    2007-06-01

    Water Users Associations (WUAs) are all too often considered a panacea for improving water management in irrigation schemes. Where grassroots movements are absent, they are usually imposed on farmers by national governments, NGOs, and international donors, without fully considering existing forms of organization. This also happened in the Office du Niger irrigation scheme in Mali, where after a partial irrigation management transfer, WUAs were created to fill the resulting power vacuum. This paper demonstrates that, despite active efforts to organize farmers in WUAs, informal patterns of decision making remain dominant. Given the shortcomings of these informal patterns, WUAs could provide a much-needed platform for institutionalizing collective action, on the condition that farmers accept them. Therefore WUAs should adopt some crucial characteristics of informal patterns of decision making while avoiding their weaknesses. First, making use of the existing authority of village leadership and the central management can improve the credibility of WUAs. Second, allowing flexibility in procedures and rules can make them more appropriate for dealing with collective action problems that are typically temporary and specific. Last, formalizing the current pattern of conflict management and sanctioning might enhance its sphere of action and tackle the current absence of firm engagement with respect to some informal management decisions. In addition, WUAs should represent and be accountable to all farmers, including those residing outside the village community.

  4. Scheme for femtosecond-resolution pump-probe experiments at XFELs with two-color ten GW-level X-ray pulses

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2010-01-01

    This paper describes a scheme for pump-probe experiments that can be performed at LCLS and at the European XFEL and determines what additional hardware development will be required to bring these experiments to fruition. It is proposed to derive both pump and probe pulses from the same electron bunch, but from different parts of the tunable-gap baseline undulator. This eliminates the need for synchronization and cancels jitter problems. The method has the further advantage to make a wide frequency range accessible at high peak-power and high repetition-rate. An important feature of the proposed scheme is that the hardware requirement is minimal. Our technique is based in essence on the ''fresh'' bunch technique. For its implementation it is sufficient to substitute a single undulator module with short magnetic delay line, i.e. a weak magnetic chicane, which delays the electron bunch with respect to the SASE pulse of half of the bunch length in the linear stage of amplification. This installation does not perturb the baseline mode of operation. We present a feasibility study and we make exemplifications with the parameters of the SASE2 line of the European XFEL. (orig.)

  5. Nuclear accidents and safety measures of domestic nuclear power plants

    International Nuclear Information System (INIS)

    Song Zurong; Che Shuwei; Pan Xiang

    2012-01-01

    Based on the design standards for the safety of nuclear and radiation in nuclear power plants, the three accidents in the history of nuclear power are analyzed. And the main factors for these accidents are found out, that is, human factors and unpredicted natural calamity. By combining the design and operation parameters of domestic nuclear plants, the same accidents are studied and some necessary preventive schemes are put forward. In the security operation technology of domestic nuclear power plants nowadays, accidents caused by human factors can by prevented completely. But the safety standards have to be reconsidered for the unpredicted neutral disasters. How to reduce the hazard of nuclear radiation and leakage to the level that can be accepted by the government and public when accidents occur under extreme conditions during construction and operation of nuclear power plants must be considered adequately. (authors)

  6. High-level nuclear waste borosilicate glass: A compendium of characteristics

    International Nuclear Information System (INIS)

    Cunnane, J.C.; Bates, J.K.; Ebert, W.L.; Feng, X.; Mazer, J.J.; Wronkiewicz, D.J.; Sproull, J.; Bourcier, W.L.; McGrail, B.P.

    1992-01-01

    With the imminent startup, in the United States, of facilities for vitrification of high-level nuclear waste, a document has been prepared that compiles the scientific basis for understanding the alteration of the waste glass products under the range of service conditions to which they may be exposed during storage, transportation, and eventual geologic disposal. A summary of selected parts of the content of this document is provided. Waste glass alterations in a geologic repository may include corrosion of the glass network due to groundwater and/or water vapor contact. Experimental testing results are described and interpreted in terms of the underlying chemical reactions and physical processes involved. The status of mechanistic modeling, which can be used for long-term predictions, is described and the remaining uncertainties associated with long-term simulations are summarized

  7. Peer review for high-level nuclear waste repositories: Generic technical position

    International Nuclear Information System (INIS)

    Altman, W.D.; Donnelly, J.P.; Kennedy, J.E.

    1988-02-01

    This document provides guidance on the use of the peer review process in the high-level nuclear waste repository program. The applicant must demonstrate in the license application that the applicable health, safety, and environmental regulations in 10 CFR Part 60 have been met. Confidence in the data used to support the license application is obtained through a quality assurance (AQ) program. Peer reviews may be used as part of the QA actions necessary to provide adequate confidence in the work being reviewed. Because of several unique conditions inherent to the geologic repository program, expert judgment will need to be utilized in assessing the adequacy of work. Peer reviews are a mechanism by which these judgments may be made. This document provides guidance on areas where a peer review is appropriate, the acceptability of peers, and the conduct and documentation of a peer review

  8. Selection criteria for container materials at the proposed Yucca Mountain high level nuclear waste repository

    International Nuclear Information System (INIS)

    Halsey, W.G.

    1989-11-01

    A geological repository has been proposed for the permanent disposal of the nation's high level nuclear waste at Yucca Mountain in the Nevada desert. The containers for this waste must remain intact for the unprecedented service lifetime of 1000 years. A combination of engineering, regulatory, and licensing requirements complicate the container material selection. In parallel to gathering information regarding the Yucca Mountain service environment and material performance data, a set of selection criteria have been established which compare candidate materials to the performance requirements, and allow a quantitative comparison of candidates. These criteria assign relative weighting to varied topic areas such as mechanical properties, corrosion resistance, fabricability, and cost. Considering the long service life of the waste containers, it is not surprising that the corrosion behavior of the material is a dominant factor. 7 refs

  9. Thermo-mechanical analysis of high level nuclear wastes in granite

    International Nuclear Information System (INIS)

    Millard, A.; Guri, G.; Raimbault, M.

    1991-01-01

    In order to appraise the safety of a storage of high level nuclear wastes in rock masses, it is necessary to assess, among other features, the thermo-mechanical behaviour of the host rock for long periods (thousands of years). In France, four different media are considered as potential host rocks: granite, shale, salt, clay. The present paper is devoted to some analysis of a generic storage configuration in granite. The case of a rock mass without any major fault has been considered. The granite is modelled by means of an elastic fracturing model (no tension type). The results obtained show that some fissures, induced by the heat generation, develop mainly above the repository. The opening of the fissures, within the frame of the adopted hypothesis, have not a strong influence on the rock mass, as a geological barrier for the radionuclides. (author)

  10. High performance gamma measurements of equipment retrieved from Hanford high-level nuclear waste tanks

    Energy Technology Data Exchange (ETDEWEB)

    Troyer, G.L.

    1997-03-17

    The cleanup of high level defense nuclear waste at the Hanford site presents several progressive challenges. Among these is the removal and disposal of various components from buried active waste tanks to allow new equipment insertion or hazards mitigation. A unique automated retrieval system at the tank provides for retrieval, high pressure washing, inventory measurement, and containment for disposal. Key to the inventory measurement is a three detector HPGe high performance gamma spectroscopy system capable of recovering data at up to 90% saturation (200,000 counts per second). Data recovery is based on a unique embedded electronic pulser and specialized software to report the inventory. Each of the detectors have different shielding specified through Monte Carlo simulation with the MCNP program. This shielding provides performance over a dynamic range of eight orders of magnitude. System description, calibration issues and operational experiences are discussed.

  11. Mechanical stability of bentonite buffer system for high level nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Lempinen, A. [Helsinki Univ. of Technology, Espoo (Finland). Lab. of Theoretical and Applied Mechanics

    1998-05-01

    According to present plans, high level nuclear waste in Finland is going to be disposed of in bedrock at a depth of several hundred metres. The spent fuel containers will be placed in boreholes drilled in the floors of deposition tunnels with engineered clay buffer, which is made of bentonite blocks. The tunnels will be filled with a mixture of bentonite and crushed rock. For stability calculations a thermomechanical model for compressed bentonite is needed. In the study a thermomechanically consistent model for reversible processes for swelling clays is presented. Preliminary calculations were performed and they show that uncertainty in material parameter values causes significantly different results. Therefore, measurements that are consistent with the model are needed 12 refs.

  12. Improved polyphase ceramic form for high-level defense nuclear waste

    International Nuclear Information System (INIS)

    Harker, A.B.; Morgan, P.E.D.; Clarke, D.R.; Flintoff, J.J.; Shaw, T.M.

    1983-01-01

    An improved ceramic nuclear waste form and fabrication process have been developed using simulated Savannah River Plant defense high-level waste compositions. The waste form provides flexibility with respect to processing conditions while exhibiting superior resistance to ground water leaching than other currently proposed forms. The ceramic, consolidated by hot-isostatic pressing at 1040 0 C and 10,000 psi, is composed of six major phases, nepheline, zirconolite, a murataite-type cubic phase, magnetite-type spinel, a magnetoplumbite solid solution, and perovskite. The waste form provides multiple crystal lattice sites for the waste elements, minimizes amorphous intergranular material, and can accommodate waste loadings in excess of 60 wt %. The fabrication of the ceramic can be accomplished with existing manufacturing technology and eliminates the effects of radionuclide volatilization and off-gas induced corrosion experienced with the molten processes for vitreous form production

  13. Natural geochemical analogues of the near field of high-level nuclear waste repositories

    International Nuclear Information System (INIS)

    Apps, J.A.

    1995-01-01

    United States practice has been to design high-level nuclear waste (HLW) geological repositories with waste densities sufficiently high that repository temperatures surrounding the waste will exceed 100 degrees C and could reach 250 degrees C. Basalt and devitrified vitroclastic tuff are among the host rocks considered for waste emplacement. Near-field repository thermal behavior and chemical alteration in such rocks is expected to be similar to that observed in many geothermal systems. Therefore, the predictive modeling required for performance assessment studies of the near field could be validated and calibrated using geothermal systems as natural analogues. Examples are given which demonstrate the need for refinement of the thermodynamic databases used in geochemical modeling of near-field natural analogues and the extent to which present models can predict conditions in geothermal fields

  14. Instrument reliability for high-level nuclear-waste-repository applications

    International Nuclear Information System (INIS)

    Rogue, F.; Binnall, E.P.; Armantrout, G.A.

    1983-01-01

    Reliable instrumentation will be needed to evaluate the characteristics of proposed high-level nuclear-wasted-repository sites and to monitor the performance of selected sites during the operational period and into repository closure. A study has been done to assess the reliability of instruments used in Department of Energy (DOE) waste repository related experiments and in other similar geological applications. The study included experiences with geotechnical, hydrological, geochemical, environmental, and radiological instrumentation and associated data acquisition equipment. Though this paper includes some findings on the reliability of instruments in each of these categories, the emphasis is on experiences with geotechnical instrumentation in hostile repository-type environments. We review the failure modes, rates, and mechanisms, along with manufacturers modifications and design changes to enhance and improve instrument performance; and include recommendations on areas where further improvements are needed

  15. Characterization of deep energy levels in mercury iodide. Application to nuclear detection

    International Nuclear Information System (INIS)

    Mohammed Brahim, Tayeb.

    1982-07-01

    The last few years have seen an increasing interest in HgI 2 detectors for room temperature gamma and X-ray spectrometry. Performance and effective thickness of these detectors are presently limited by carrier trapping which results in incomplete charge collection. Characterization of the trapping levels has been performed by several photoelectronic methods (photoconductivity, thermal and optical quenching of the photoconductivity, TSC, lifetime measurement). A model is proposed taking into account the results obtained by these techniques and the polarization phenomena observed in nuclear detection in both vapor phase and solution grown crystals. For the latter, polarization can be eliminated or notably reduced by illumination of the positive electrode or by using a MIS positively biased structure [fr

  16. Heat transfer effects in vertically emplaced high level nuclear waste container

    International Nuclear Information System (INIS)

    Moujaes, S.F.; Lei, Y.M.

    1994-01-01

    Modeling free convection heat transfer in an cylindrical annular enclosure is still an active area of research and an important problem to be addressed in the high level nuclear waste repository. For the vertically emplaced waste container, the air gap which is between the container shell and the rock borehole, have an important role of dissipating heat to surrounding rack. These waste containers are vertically emplaced in the borehole 300 meters below ground, and in a horizontal grid of 30 x 8 meters apart. The borehole will be capped after the container emplacement. The expected initial heat generated is between 3--4.74 kW per container depending on the type of waste. The goal of this study is to use a computer simulation model to find the borehole wall, air-gap and the container outer wall temperature distributions

  17. Mechanical stability of bentonite buffer system for high level nuclear waste

    International Nuclear Information System (INIS)

    Lempinen, A.

    1998-05-01

    According to present plans, high level nuclear waste in Finland is going to be disposed of in bedrock at a depth of several hundred metres. The spent fuel containers will be placed in boreholes drilled in the floors of deposition tunnels with engineered clay buffer, which is made of bentonite blocks. The tunnels will be filled with a mixture of bentonite and crushed rock. For stability calculations a thermomechanical model for compressed bentonite is needed. In the study a thermomechanically consistent model for reversible processes for swelling clays is presented. Preliminary calculations were performed and they show that uncertainty in material parameter values causes significantly different results. Therefore, measurements that are consistent with the model are needed

  18. Selective removal of cesium and strontium using porous frameworks from high level nuclear waste.

    Science.gov (United States)

    Aguila, Briana; Banerjee, Debasis; Nie, Zimin; Shin, Yongsoon; Ma, Shengqian; Thallapally, Praveen K

    2016-05-01

    Efficient and cost-effective removal of radioactive (137)Cs and (90)Sr found in spent fuel is an important step for safe, long-term storage of nuclear waste. Solid-state materials such as resins and titanosilicate zeolites have been assessed for the removal of Cs and Sr from aqueous solutions, but there is room for improvement in terms of capacity and selectivity. Herein, we report the Cs(+) and Sr(2+) exchange potential of an ultra stable MOF, namely, MIL-101-SO3H, as a function of different contact times, concentrations, pH levels, and in the presence of competing ions. Our preliminary results suggest that MOFs with suitable ion exchange groups can be promising alternate materials for cesium and strontium removal.

  19. High performance gamma measurements of equipment retrieved from Hanford high-level nuclear waste tanks

    International Nuclear Information System (INIS)

    Troyer, G.L.

    1997-01-01

    The cleanup of high level defense nuclear waste at the Hanford site presents several progressive challenges. Among these is the removal and disposal of various components from buried active waste tanks to allow new equipment insertion or hazards mitigation. A unique automated retrieval system at the tank provides for retrieval, high pressure washing, inventory measurement, and containment for disposal. Key to the inventory measurement is a three detector HPGe high performance gamma spectroscopy system capable of recovering data at up to 90% saturation (200,000 counts per second). Data recovery is based on a unique embedded electronic pulser and specialized software to report the inventory. Each of the detectors have different shielding specified through Monte Carlo simulation with the MCNP program. This shielding provides performance over a dynamic range of eight orders of magnitude. System description, calibration issues and operational experiences are discussed

  20. Can state-level safeguards be applied in nuclear weapon states?

    Energy Technology Data Exchange (ETDEWEB)

    Listner, Clemens; Canty, Morton J. [Forschungszentrum Juelich (Germany); Rezniczek, Arnold [UBA GmbH, Herzogenrath (Germany); Stein, Gotthard

    2013-07-01

    Acquisition Path Analysis (APA) is a key element of IAEA's State-level concept. Currently, this process is mainly based on expert judgment. However, the requirements from the IAEA state that the process must be objective, reproducible, transparent, standardized, documented and as a result non-discriminatory. A formal approach fulfilling these requirements has been set up by the authors in the past. In this paper, the refined methodology is presented. Improvements have been made in the interface definition between the three stages, the general network model has been updated, and the automatic visualization of acquisition paths has been accomplished. Furthermore, a prototype implementation will be shown. Based on this methodology, a test case example is presented which models a hypothetic nuclear weapon State not having signed the NPT. For this case, it will be shown how APA can be implemented using the proposed methodology.

  1. Seismic design ampersand analysis considerations for high level nuclear waste repositories

    International Nuclear Information System (INIS)

    Hossain, Q.A.

    1993-01-01

    A high level nuclear waste repository, like the one at Nevada's Yucca Mountain that is being investigated for site suitability, will have some unique seismic design and analysis considerations. These are discussed, and a design philosophy that can rationally account for the unique performance objectives of such facilities is presented. A case is made for the use of DOE's performance goal-based seismic design and evaluation methodology that is based on a hybrid open-quotes deterministicclose quotes and open-quotes probabilisticclose quotes concept. How and to what extent this methodology should be modified to adopt it for a potential site like Yucca Mountain is also outlined. Finally, the issue of designing for seismic fault rupture is discussed briefly, and the desirability of using the proposed seismic design philosophy in fault rupture evaluation is described

  2. Seismic design and analysis considerations for high level nuclear waste repositories

    International Nuclear Information System (INIS)

    Hossain, Q.A.

    1993-01-01

    A high level nuclear waste repository, like the one at Nevada's Yucca Mountain that is being investigated for site suitability, will have some unique seismic design and analysis considerations. These are discussed, and a design philosophy that can rationally account for the unique performance objectives of such facilities is presented. A case is made for the use of DOE's performance goal-based seismic design and evaluation methodology that is based on a hybrid ''deterministic'' and ''probabilistic'' concept. How and to what extent this methodology should be modified to adopt it for a potential site like Yucca Mountain is also outlined. Finally, the issue of designing for seismic fault rupture is discussed briefly, and the desirability of using the proposed seismic design philosophy in fault rupture evaluation is described

  3. Operational intervention levels in a nuclear emergency, general concepts and a probabilistic approach

    International Nuclear Information System (INIS)

    Lauritzen, B.; Baeverstam, U.; Naadland Holo, E.; Sinkko, K.

    1997-12-01

    This report deals with Operational Intervention Levels (OILs) in a nuclear or radiation emergency. OILs are defined as the values of environmental measurements, in particular dose rate measurements, above which specific protective actions should be carried out in emergency exposure situations. The derivation and the application of OILs are discussed, and an overview of the presently adopted values is provided, with emphasis on the situation in the Nordic countries. A new, probabilistic approach to derive OILs is presented and the method is illustrated by calculating dose rate OILs in a simplified setting. Contrary to the standard approach, the probabilistic approach allows for optimization of OILs. It is argued, that optimized OILs may be much larger than the presently adopted or suggested values. It is recommended, that the probabilistic approach is further developed and employed in determining site specific OILs and in optimizing environmental measuring strategies. (au)

  4. A conceptual subsurface facility design for a high-level nuclear waste repository at Yucca Mountain

    International Nuclear Information System (INIS)

    McKenzie, D.G., III; Bhattacharyya, K.K.; Segrest, A.M.

    1996-01-01

    The US Department of Energy is responsible for the design, construction, operation and closure of a repository in which to permanently dispose of the nation's high level nuclear waste. In addition to the objective of safely isolating the waste inventory, the repository must provide a safe working environment for its workforce, and protect the public. The conceptual design for this facility is currently being developed. Tunnel Boring Machine will be used to excavate 228 kilometers of tunneling to construct the facility over a 30 year period. The excavation operations will be physically separated from the waste emplacement operations, and each operation will have its own dedicated ventilation system. The facility is being designed to remain open for 150 years

  5. Spent nuclear fuel and high level radioactive waste transportation. White paper

    International Nuclear Information System (INIS)

    1985-06-01

    The High-Level Radioactive Waste Committee of the Western Interstate Energy Board has been involved in a year-long cooperative project with the US Department of Energy (DOE) to develop an information base on the transportation of spent nuclear fuel and high-level radioactive waste (HLW) so that western states can be constructive and informed participants in the repository program under the Nuclear Waste Policy Act (NWPA). The historical safety record of transportation of HLW and spent fuel is excellent; no release of these radioactive materials has ever occurred during transportation. Projected shipments under the NWPA will, however, greatly exceed current shipments in the US. For example, over the past five years, 119 metric tons of civilian spent fuel have been shipped in this country, while shipments to the first and second repository are each expected to peak at 3000 metric tons per year. The Committee believes that the successful development and operation of a national HLW/spent fuel transportation system can best be accomplished through an open process based on the common sense approach of taking all reasonable measures to minimize public risk and performing whatever actions are reasonably required to promote public acceptance. Therefore, the Committee recommends that the Department of Energy further the goals of the NWPA by developing a Comprehensive Transportation Plan which adopts a systematic, comprehensive, and integrated approach to resolving all spent fuel and HLW transportation issues in a timely manner. The suggested scope of such a plan is discussed in this White paper. Many of the suggested elements of such a plan are similar to those being developed by the Department of energy for inclusion in the Department's Transportation Institutional Plan

  6. Xanthophylls increased HDLC level and nuclear factor PPARγ, RXRγ and RARα expression in hens and chicks.

    Science.gov (United States)

    Gao, Y-Y; Jin, L; Peng, H; Xu, L-H; Wang, Q-X; Ji, J; Wang, C-K; Bi, Y-Z

    2018-02-01

    This study was designed to investigate effects of xanthophylls on serum lipid profile (triglyceride, TG; cholesterol, CHO; high-density lipoprotein cholesterol, HDLC; and low-density lipoprotein cholesterol, LDLC) and nuclear factor (peroxisome proliferator-activated receptor gamma, PPARγ; PPAR gamma coactivator 1 alpha, PGC1α; retinoid X receptor gamma, RXRγ; and retinoic acid receptor alpha, RARα) gene expression of breeding hens and chicks. In experiment 1, 432 hens were divided into three groups and fed diets supplemented with 0 (as control group), 20 or 40 mg/kg xanthophylls. Blood was sampled at 7, 14, 21, 28 and 35 days of trial. Liver, duodenum, jejunum and ileum were sampled at 35 days of trial. Results showed that serum HDLC level of hens was increased after dietary 40 mg/kg xanthophyll addition for 21, 28 and 35 days, while serum TG, CHO and LDLC were not affected. Xanthophyll addition also increased PPARγ expression in jejunum, RXRγ expression in duodenum and jejunum, and RARα expression in liver and duodenum. Experiment 2 was a 2 × 2 factorial design. Male chicks hatched from 0 or 40 mg/kg xanthophyll diet of hens were fed diet containing either 0 or 40 mg/kg xanthophylls. Liver, duodenum, jejunum and ileum were sampled at 0, 7, 14 and 21 days after hatching. Blood samples were also collected at 21 days. Results showed that in ovo xanthophylls elevated PPARγ in duodenum and jejunum, and RXRγ and RARα in liver of chicks mainly within 1 week after hatching, while dietary xanthophylls increased serum HDLC level and PPARγ and RXRγ in liver from 2 weeks onwards. In conclusion, our research suggested xanthophylls can regulate serum lipid profile and nuclear factor expression in hens and chicks. © 2017 Blackwell Verlag GmbH.

  7. Improvement of Level-1 PSA computer code package -A study for nuclear safety improvement-

    International Nuclear Information System (INIS)

    Park, Chang Kyu; Kim, Tae Woon; Ha, Jae Joo; Han, Sang Hoon; Cho, Yeong Kyun; Jeong, Won Dae; Jang, Seung Cheol; Choi, Young; Seong, Tae Yong; Kang, Dae Il; Hwang, Mi Jeong; Choi, Seon Yeong; An, Kwang Il

    1994-07-01

    This year is the second year of the Government-sponsored Mid- and Long-Term Nuclear Power Technology Development Project. The scope of this subproject titled on 'The Improvement of Level-1 PSA Computer Codes' is divided into three main activities : (1) Methodology development on the under-developed fields such as risk assessment technology for plant shutdown and external events, (2) Computer code package development for Level-1 PSA, (3) Applications of new technologies to reactor safety assessment. At first, in the area of PSA methodology development, foreign PSA reports on shutdown and external events have been reviewed and various PSA methodologies have been compared. Level-1 PSA code KIRAP and CCF analysis code COCOA are converted from KOS to Windows. Human reliability database has been also established in this year. In the area of new technology applications, fuzzy set theory and entropy theory are used to estimate component life and to develop a new measure of uncertainty importance. Finally, in the field of application study of PSA technique to reactor regulation, a strategic study to develop a dynamic risk management tool PEPSI and the determination of inspection and test priority of motor operated valves based on risk importance worths have been studied. (Author)

  8. Invention principles and levels in the event of a nuclear accident

    International Nuclear Information System (INIS)

    Walmod-Larsen, O.

    1994-01-01

    In order to promote Nordic harmonization of the most likely protective measures to be taken in the case of large nuclear accidents, this report presents the background material needed to make common decisions on sheltering, evacuation and relocation. Brief comments only are also made on iodine prophylaxis and foodstuff restrictions. Viewing the national monetary costs per person for such measures in relation to the income per capita - and in relation to the currency exchange rates of Feb. 1994 - there are by and large no arguments to find for different intervention levels in any of the four countries, DK, NO, FI and SE. As applied α-values (the estimated monetary cost of a man-Sievert) are observed to have a large range, attempts were made to find the economic value of a health detriment. These pointed to the Willingness-To-Pay method, and a pilot project was performed in Denmark. On this basis a set of intervention levels - similar to internationally recommended levels -is proposed. Other factors influencing decisions in emergency situations are discussed. Risk perception, risk communication and psychological factors, as well as the modern decision-aiding tools capable of handling such factors are also described. (au) (47 refs.)

  9. Selection of candidate canister materials for high-level nuclear waste containment in a tuff repository

    International Nuclear Information System (INIS)

    McCright, R.D.; Weiss, H.; Juhas, M.C.; Logan, R.W.

    1983-11-01

    A repository located at Yucca Mountain at the Nevada Test Site is a potential site for permanent geological disposal of high-level nuclear waste. The repository can be located in a horizon in welded tuff, a volcanic rock, which is above the static water level at this site. The environmental conditions in this unsaturated zone are expected to be air and water vapor dominated for much of the containment period. Type 304L stainless steel is the reference material for fabricating canisters to contain the solid high-level wastes. Alternative stainless alloys are considered because of possible susceptibility of 304L to localized and stress forms of corrosion. For the reprocessed glass wastes, the canisters serve as the recipient for pouring the glass with the result that a sensitized microstructure may develop because of the times at elevated temperatures. Corrosion testing of the reference and alternative materials has begun in tuff-conditioned water and steam environments. 21 references, 8 figures, 8 tables

  10. Pulse superimposition calculational methodology for estimating the subcriticality level of nuclear fuel assemblies

    International Nuclear Information System (INIS)

    Talamo, Alberto; Gohar, Y.; Rabiti, C.; Aliberti, G.; Kondev, F.; Smith, D.; Zhong, Z.; Kiyavitskaya, H.; Bournos, V.; Fokov, Y.; Routkovskaya, C.; Serafimovich, I.

    2009-01-01

    One of the most reliable experimental methods for measuring the subcriticality level of a nuclear fuel assembly is the Sjoestrand method applied to the reaction rate generated from a pulsed neutron source. This study developed a new analytical methodology simulating the Sjoestrand method, which allows comparing the experimental and analytical reaction rates and the obtained subcriticality levels. In this methodology, the reaction rate is calculated due to a single neutron pulse using MCNP/MCNPX computer code or any other neutron transport code that explicitly simulates the delayed fission neutrons. The calculation simulates a single neutron pulse over a long time period until the delayed neutron contribution to the reaction rate is vanished. The obtained reaction rate is then superimposed to itself, with respect to the time, to simulate the repeated pulse operation until the asymptotic level of the reaction rate, set by the delayed neutrons, is achieved. The superimposition of the pulse to itself was calculated by a simple C computer program. A parallel version of the C program is used due to the large amount of data being processed, e.g. by the Message Passing Interface (MPI). The analytical results of this new calculation methodology have shown an excellent agreement with the experimental data available from the YALINA-Booster facility of Belarus. This methodology can be used to calculate Bell and Glasstone spatial correction factor.

  11. Pulse superimposition calculational methodology for estimating the subcriticality level of nuclear fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Talamo, Alberto [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)], E-mail: atalamo@anl.gov; Gohar, Y. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Rabiti, C. [Idaho National Laboratory, P.O. Box 2528, Idaho Falls, ID 83403 (United States); Aliberti, G.; Kondev, F.; Smith, D.; Zhong, Z. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Kiyavitskaya, H.; Bournos, V.; Fokov, Y.; Routkovskaya, C.; Serafimovich, I. [Joint Institute for Power and Nuclear Research-Sosny, National Academy of Sciences (Belarus)

    2009-07-21

    One of the most reliable experimental methods for measuring the subcriticality level of a nuclear fuel assembly is the Sjoestrand method applied to the reaction rate generated from a pulsed neutron source. This study developed a new analytical methodology simulating the Sjoestrand method, which allows comparing the experimental and analytical reaction rates and the obtained subcriticality levels. In this methodology, the reaction rate is calculated due to a single neutron pulse using MCNP/MCNPX computer code or any other neutron transport code that explicitly simulates the delayed fission neutrons. The calculation simulates a single neutron pulse over a long time period until the delayed neutron contribution to the reaction rate is vanished. The obtained reaction rate is then superimposed to itself, with respect to the time, to simulate the repeated pulse operation until the asymptotic level of the reaction rate, set by the delayed neutrons, is achieved. The superimposition of the pulse to itself was calculated by a simple C computer program. A parallel version of the C program is used due to the large amount of data being processed, e.g. by the Message Passing Interface (MPI). The analytical results of this new calculation methodology have shown an excellent agreement with the experimental data available from the YALINA-Booster facility of Belarus. This methodology can be used to calculate Bell and Glasstone spatial correction factor.

  12. Neural Network with Local Memory for Nuclear Reactor Power Level Control

    International Nuclear Information System (INIS)

    Uluyol, Oender; Ragheb, Magdi; Tsoukalas, Lefteri

    2001-01-01

    A methodology is introduced for a neural network with local memory called a multilayered local output gamma feedback (LOGF) neural network within the paradigm of locally-recurrent globally-feedforward neural networks. It appears to be well-suited for the identification, prediction, and control tasks in highly dynamic systems; it allows for the presentation of different timescales through incorporation of a gamma memory. A learning algorithm based on the backpropagation-through-time approach is derived. The spatial and temporal weights of the network are iteratively optimized for a given problem using the derived learning algorithm. As a demonstration of the methodology, it is applied to the task of power level control of a nuclear reactor at different fuel cycle conditions. The results demonstrate that the LOGF neural network controller outperforms the classical as well as the state feedback-assisted classical controllers for reactor power level control by showing a better tracking of the demand power, improving the fuel and exit temperature responses, and by performing robustly in different fuel cycle and power level conditions

  13. Assessing and Promoting the Level of Safeguards Culture in Hungarian Nuclear Facilities

    International Nuclear Information System (INIS)

    Stefanka, Z.; Vincze, A.

    2015-01-01

    The Hungarian SSAC has introduced a comprehensive domestic safeguards verification system consisting of regular comprehensive SSAC verifications in the whole lifetime of the facilities. The main goals of the comprehensive verification system are: (i) to assess the facility's safeguards system compliance with the relevant national legislation and recommendations, (ii) to assess the activities of the facility aimed at maintaining and further developing its safeguards system, and, (iii) to revise validity of data and information previously provided by the facility subject to safeguards licencing procedures. The maintenance level of the system as well as the available knowledge on the possible needs for change reflect the top management's awareness of this issue and is a good indicator of the present and future effectiveness of the facility level safeguards system and the level of safeguards culture. The structure, preparation, conduction, documentation and initial experiences of the comprehensive safeguards verification system is introduced in the paper. Additionally, HAEA has just introduced a safeguards indexing method for evaluation the safeguards culture at Hungarian nuclear facilities. The main goal of indexing method and the evaluated parameters are also shown in the paper. (author)

  14. Detailed description of a state system for accounting for and control of nuclear material at the state level

    International Nuclear Information System (INIS)

    Jones, R.J.

    1985-02-01

    The purpose of this document is to provide a detailed description of the technical elements of a system for the accounting for and control of nuclear material at the State Authority level which can be used by a state in the establishment of a national system for nuclear material accounting and control. It is expected that a state system designed along the lines described also will assist the IAEA in carrying out its safeguards responsibilities. The scope of this document is limited to descriptions of the technical elements of a state level system concerned with Laws and Regulations, the Information System, and the Establishment of Requirements for Nuclear Material Accounting and Control. The discussion shows the relationship of these technical elements at the state level to the principal elements of an SSAC at the facility levels

  15. Nuclear

    International Nuclear Information System (INIS)

    2014-01-01

    This document proposes a presentation and discussion of the main notions, issues, principles, or characteristics related to nuclear energy: radioactivity (presence in the environment, explanation, measurement, periods and activities, low doses, applications), fuel cycle (front end, mining and ore concentration, refining and conversion, fuel fabrication, in the reactor, back end with reprocessing and recycling, transport), the future of the thorium-based fuel cycle (motivations, benefits and drawbacks), nuclear reactors (principles of fission reactors, reactor types, PWR reactors, BWR, heavy-water reactor, high temperature reactor of HTR, future reactors), nuclear wastes (classification, packaging and storage, legal aspects, vitrification, choice of a deep storage option, quantities and costs, foreign practices), radioactive releases of nuclear installations (main released radio-elements, radioactive releases by nuclear reactors and by La Hague plant, gaseous and liquid effluents, impact of releases, regulation), the OSPAR Convention, management and safety of nuclear activities (from control to quality insurance, to quality management and to sustainable development), national safety bodies (mission, means, organisation and activities of ASN, IRSN, HCTISN), international bodies, nuclear and medicine (applications of radioactivity, medical imagery, radiotherapy, doses in nuclear medicine, implementation, the accident in Epinal), nuclear and R and D (past R and D programmes and expenses, main actors in France and present funding, main R and D axis, international cooperation)

  16. An analysis of the properties of levelized cost analysis of storage or recycling of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Vergueiro, Sophia M. C.; Ramos, Alexandre F., E-mail: alex.ramos@usp.br, E-mail: sophia.vergueiro@usp.br [Universidade de São Paulo (USP), SP (Brazil). Núcleo Interdisciplinar de Modelagem de Sistemas Complexos

    2017-07-01

    The demand for reduction of carbon dioxide emissions in the processes of electricity generation, plus the demand for firm energy matrices, make the nuclear matrix a central component to occupy the energy mix during the next hundred years. Increasing the share of nuclear power in electricity production in a multiple developing countries will lead to increased spent fuel production. Thus, the managing radioactive waste aiming to decide about storing or recycling it is a central issue to be addressed by environmental management and nuclear energy communities. In this manuscript we present our studies aiming to understand the levelized analysis of cost of electricity generation comparing storage or recycling of the spent fuel. (author)

  17. An analysis of the properties of levelized cost analysis of storage or recycling of spent nuclear fuel

    International Nuclear Information System (INIS)

    Vergueiro, Sophia M. C.; Ramos, Alexandre F.

    2017-01-01

    The demand for reduction of carbon dioxide emissions in the processes of electricity generation, plus the demand for firm energy matrices, make the nuclear matrix a central component to occupy the energy mix during the next hundred years. Increasing the share of nuclear power in electricity production in a multiple developing countries will lead to increased spent fuel production. Thus, the managing radioactive waste aiming to decide about storing or recycling it is a central issue to be addressed by environmental management and nuclear energy communities. In this manuscript we present our studies aiming to understand the levelized analysis of cost of electricity generation comparing storage or recycling of the spent fuel. (author)

  18. Nucleocytoplasmic shuttling mediates the dynamic maintenance of nuclear Dorsal levels during Drosophila embryogenesis

    DEFF Research Database (Denmark)

    DeLotto, Robert; DeLotto, Yvonne; Steward, Ruth

    2007-01-01

    , including nuclei on the dorsal side. Nuclear export is blocked by leptomycin B, a potent inhibitor of Exportin 1 (CRM1)-mediated nuclear export. We have developed a novel in vivo assay revealing the presence of a functional leucine-rich nuclear export signal within the carboxyterminal 44 amino acids...

  19. Development of geopolymers as candidate materials for low/intermediate level highly alkaline nuclear waste

    International Nuclear Information System (INIS)

    Perera, D.S.; Vance, E.R.; Kiyama, S.; Aly, Z.; Yee, P.

    2006-01-01

    Full text: Geopolymers have been studied for many years as a possible improvement on cement in respect of compressive strength, resistance to fire, heat and acidity, and as a medium for the encapsulation of hazardous or low/ intermediate level radioactive waste. They are made by adding aluminosilicates to concentrated alkali solutions and the application of heat at 0 Cfor subsequent polymerisation. In this work we studied them as suitable candidate materials to incorporate NaOH/NaA10 2 containing waste with low levels of Cs, Sr and Nd. Geopolymers were produced by incorporating the highly alkaline solution as part of the composition with added metakaolinite, fumed silica and extra NaOH, such that the overall geopolymer composition was of molar ratios Si/Al = 2 and Na/Al = 1. The simulated waste contained Na2SO 4 , therefore Ba(OH) 2 was also added to precipitate the SO 4 x 2 as BaSO 4 . Three geoplymers of the same composition containing simulated wastes were leach tested in triplicate after heating at 400 0 Cfor 1 h (to remove -98% of free and interstitial water) under the PCT-B test protocol at 90 0 Cfor 7 days and their results are listed in Table 1. The Cs, Sr and Nd normalised leach rates were low. The Na leach rate was ∼ 4 g/L thus passing the PCT-B test protocol value of 13.5 g/L for EA glass. The X-ray diffraction and scanning electron microscopy showed that BaS04 did precipitate, however all the S did not appear to have precipitated. The ANSI/ANS-16.1-2003 test was carried out on the above geopolymer composition for 5 days. The ANSI Leachability Index D (diffusivity of 10''cm sec'') for the elements released are listed in Table 2. A Portland cement was also tested for comparison and the Leachability index values are 11, 8 and 10 for Al, Na and Ca respectively. Both passed the test protocol insofar as they were > 6. Geopolymers thus passing the tests for high level nuclear waste glass (PCT-B) and for low level nuclear waste (ANSI) show promising potential

  20. Pancreas Oxygen Persufflation Increases ATP Levels as Shown by Nuclear Magnetic Resonance

    Science.gov (United States)

    Scott, W.E.; Weegman, B.P.; Ferrer-Fabrega, J.; Stein, S.A.; Anazawa, T.; Kirchner, V.A.; Rizzari, M.D.; Stone, J.; Matsumoto, S.; Hammer, B.E.; Balamurugan, A.N.; Kidder, L.S.; Suszynski, T.M.; Avgoustiniatos, E.S.; Stone, S.G.; Tempelman, L.A.; Sutherland, D.E.R.; Hering, B.J.; Papas, K.K.

    2010-01-01

    Background Islet transplantation is a promising treatment for type 1 diabetes. Due to a shortage of suitable human pancreata, high cost, and the large dose of islets presently required for long-term diabetes reversal; it is important to maximize viable islet yield. Traditional methods of pancreas preservation have been identified as suboptimal due to insufficient oxygenation. Enhanced oxygen delivery is a key area of improvement. In this paper, we explored improved oxygen delivery by persufflation (PSF), ie, vascular gas perfusion. Methods Human pancreata were obtained from brain-dead donors. Porcine pancreata were procured by en bloc viscerectomy from heparinized donation after cardiac death donors and were either preserved by either two-layer method (TLM) or PSF. Following procurement, organs were transported to a 1.5-T magnetic resonance (MR) system for 31P nuclear magnetic resonance spectroscopy to investigate their bioenergetic status by measuring the ratio of adenosine triphosphate to inorganic phosphate (ATP:Pi) and for assessing PSF homogeneity by MRI. Results Human and porcine pancreata can be effectively preserved by PSF. MRI showed that pancreatic tissue was homogeneously filled with gas. TLM can effectively raise ATP:Pi levels in rat pancreata but not in larger porcine pancreata. ATP:Pi levels were almost undetectable in porcine organs preserved with TLM. When human or porcine organs were preserved by PSF, ATP:Pi was elevated to levels similar to those observed in rat pancreata. Conclusion The methods developed for human and porcine pancreas PSF homogeneously deliver oxygen throughout the organ. This elevates ATP levels during preservation and may improve islet isolation outcomes while enabling the use of marginal donors, thus expanding the usable donor pool. PMID:20692395