Energy Technology Data Exchange (ETDEWEB)

We prove that the 1984 protocol of Bennett and Brassard (BB84) for quantum key distribution is secure. We first give a key distribution protocol based on entanglement purification, which can be proven secure using methods from Lo and Chau's proof of security for a similar protocol. We then show that the security of this protocol implies the security of BB84. The entanglement purification based protocol uses Calderbank-Shor-Steane codes, and properties of these codes are used to remove the use of quantum computation from the Lo-Chau protocol. (c) 2000 The American Physical Society.

British Library Electronic Table of Contents (United Kingdom)

Abstract This study presents a review of distributed model predictive control (DMPC) strategies followed by recent studies conducted by the authors on the robustness of these strategies to model errors and a summary of future challenges in this area. The review identifies three key challenges for the successful application of DMPC: (i) the selection of optimal control structure for DMPC; (ii) the choice of a suitable coordination strategy among the controllers; and (iii) the robustness of DMPC strategies to model errors. Then, the study summarises recent developments related to the robustness of unconstrained and constrained DMPC algorithms. For the unconstrained case, a methodology that is based on the calculation of a performance index is proposed to balance the trade-off between perform...

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of ...

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential ...

British Library Electronic Table of Contents (United Kingdom)

Concerns for potential vulnerability to manganese (Mn) neurotoxicity during fetal and neonatal development have been raised due to increased needs for Mn for normal growth, different sources of exposure to Mn, and pharmacokinetic differences between the young and adults. A physiologically based pharmacokinetic (PBPK) model for Mn during human gestation and lactation was developed to predict Mn in fetal and neonatal brain using a parallelogram approach based upon extrapolation across life stages in rats and cross-species extrapolation to humans. Based on the rodent modeling, key physiological processes controlling Mn kinetics during gestation and lactation were incorporated, including alterations in Mn uptake, excretion, tissue-specific distributions, and placental and lactational transfer ...

CERN Document Server

Because of the stochastic nature of traffic requirement matrix, it is very difficult to get the optimal traffic distribution to minimize the delay even with adaptive routing protocol in a fixed connection network where capacity already defined for each link. Hence there is a requirement to define such a method, which could generate the optimal solution very quickly and efficiently. This paper presenting a new concept to provide the adaptive optimal traffic distribution for dynamic condition of traffic matrix using nature based intelligence methods. With the defined load and fixed capacity of links, average delay for packet has minimized with various variations of evolutionary programming and particle swarm optimization. Comparative study has given over their performance in terms of converging speed. Universal approximation capability, the key feature of feed forward neural network has applied to predict ...

International Nuclear Information System (INIS)

A measuring-basis encrypted quantum key distribution scheme is proposed by using twelve nonorthogonal states in a four-state system and the measuring-basis encryption technique. In this scheme, two bits of classical information can be encoded on one four-state particle and the transmitted particles can be fully used.

Energy Technology Data Exchange (ETDEWEB)

Four interrelated projects are underway whose purpose is to migrate the LAMPF-PSR Accelerator Complex control systems to a system with a common set of hardware and software components. Project goals address problems in performance, maintenance and growth potential. Front-end hardware, operator interface hardware and software, computer systems, network systems and data system software are being simultaneously upgraded as part of these efforts. The efforts are being coordinated to provide for a smooth and timely migration to a client-sever model-based data acquisition and control system. An increased use of the distributed intelligence at both the front-end and operator interface is a key element of the projects. 2 refs., 2 figs.

CERN Document Server

Real-time digital libraries based on widely distributed, high performance management of large-data-objects

Science.gov (United States)

... BAE Systems Advanced Information Technologies, Inc. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. ...

CERN Document Server

Heterogeneous base stations (e.g. picocells, microcells, femtocells and distributed antennas) will become increasingly essential for cellular network capacity and coverage. Up until now, little basic research has been done on the fundamentals of managing so much infrastructure -- much of it unplanned -- together with the carefully planned macro-cellular network. Inter-cell coordination is in principle an effective way of ensuring different infrastructure components behave in a way that increases, rather than decreases, the key quality of service (QoS) metrics. The success of such coordination depends heavily on how the overhead is shared, and the rate and delay of the overhead sharing. We develop a novel framework to quantify overhead signaling for inter-cell coordination, which is usually ignored in traditional 1-tier networks, and assumes even more importance in multi-tier heterogeneous cellular networks (HCNs). We derive ...

Energy Technology Data Exchange (ETDEWEB)

This work describes the development of a synchronous key based on micro controller to the switching of three-phase power transformers, which makes possible the achievement of tests to register the inrush current, and the previous establishment of the instantaneous values of the voltage firstly applied to different phases of the energy process. This key is a value tool to the development electric power system projects and to the teaching and researching activities at the laboratory related to transitory phenomena and electric system protection.

UK PubMed Central (United Kingdom)

BackgroundDue to the high morbidity and mortality of fulminant hepatitis, early diagnosis followed by early effective treatment is the key for prognosis improvement. So far, little...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundStable transgenesis is an undeniable key to understanding any genetic system. Retrovirus-based insertional strategies, which feature several technical challenges when they...Full Text Available

International Nuclear Information System (INIS)

Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.

Energy Technology Data Exchange (ETDEWEB)

Eddy current testing (ECT) method is widely used as the non-destructive evaluation (NDE) of the various kinds of material degradation occurring in nuclear power plants (NPPs) components including steam generator (SG) tubes. Detection of any defects or flaws in the steam generator tubes in the early stage is very important in maintenance of NPP for its primary role as the pressure boundary with thin wall thickness. Although the ECT technique provides lots of information for a SG management, it has a generic problem in its reliability due to a low ability in detect of small defects and some difficulty in a signal analysis. For the improvement of these shortcomings in conventional ECT, profile-MRPC (motorized rotating pancake coil) ECT technology was developed in KAERI. The key of this new technology is the development of new eddy current probes, designated as a diagnostic probe (D-probe). The D-probe is furnished with a simultaneous dual function of a defect ...

Energy Technology Data Exchange (ETDEWEB)

Radon migration in porous, earthen materials is characterized by diffusion in both the air and water components of the system as well as by the interaction of the radon between the air and water. The size distribution and configuration of the pore spaces and their moisture distributions are key parameters in determining the radon diffusion coefficient for the bulk material. A mathematical model is developed and presented for calculating radon diffusion coefficients solely from the moisture content and pore size distribution of a soil, reducing the need for resorting to radon diffusion measurements. The resulting diffusion coefficients increase with the median pore diameter of the soil and decrease with increasing widths of the pore size distribution. The calculated diffusion coefficients are suitable for use in simple homogeneous-medium diffusion expressions for predicting radon ...

Energy Technology Data Exchange (ETDEWEB)

Fission rate assessments are being made in FFTF to provide input for determination of power distribution, peak power, total power, fuel burnup distribution, conversion ration and neutron spectral information by the multiple foil reaction rate method. A goal of the initial FFTF Characterization Program is to measure isotopic fission rates to an accuracy of 2 to 5% throughout FFTF by radiometric techniques. To achieve this goal, measurements were made in the FFTF In-Reactor Thimble to reduce the uncertainties of key parameters needed for radiometric fission rate mapping of the FFTF core.

International Nuclear Information System (INIS)

To further optimize thermo-hydraulic capability of HCSB-TBM, two different thermo-hydraulic schemes would be proposed and investigated by relevant calculating and simulating of thermo-dynamics in normal and peak heat flux condition. With computational fluid dynamics (CFD) code FLUENT, the actual temperature distribution of key components of HCSB-TBM is simulated. (authors)

Energy Technology Data Exchange (ETDEWEB)

Thermal absorption with its combined thermal and mechanical loads in a solar receiver does depend significantly on the distribution of incident solar radiation. For a cavity receiver with paraboloid collectar a method is derived which enables the calculation of solar radiation distribution on the areas inside the receiver. The theoretical bases are presented first, and a subsequent example shows the influence of the most important geometric parameters on the distribution of solar radiation.

Energy Technology Data Exchange (ETDEWEB)

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of {sup 137}Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). Samples of the exchangers were irradiated ...

British Library Electronic Table of Contents (United Kingdom)

Purpose - Key account management (KAM) programmes are a way for companies to develop existing relationships and increase sales, thus being proactive and searching for opportunities (which is often expected of KAM). It is also a way to meet changing customer demands arising from changes in purchasing strategy, buyers' mergers and acquisitions and the search for synergies in order to reduce costs. The purpose of this article is to analyse different key account management programmes on how they manage the sales process complexity and customer expectations. Design/methodology/approach - The paper draws on qualitative data collected during a field study of ABB and six of their major customers, based on annual or biannual interviews with 50 individuals within ABB from 1996 to 2006 and three to t...

British Library Electronic Table of Contents (United Kingdom)

The phenomenon of key supply management (KSM) in business companies is far less investigated than the phenomenon of key account management (KAM) which beneficiates, both in practice and in an academic context, from a growing interest. This article is based on the empirical analysis of a sample of 10 international companies which have recently launched KSM programmes or are currently working on launching such programs. It examines the difficulties these companies come up against when implementing such programmes and proposes to organize these difficulties around three dimensions: 1) the difficulties in implementing real supplier portfolio approaches; 2) the narrow view of value co-creation with suppliers, and 3) the persistent lack of integration of the purchasing function with other intern...

International Nuclear Information System (INIS)

Method for description of X-ray radiation dose distribution based on semiempirical description of dose fields is suggested. At that dose field description parameters can be easily individualized for concrete X-ray device.

British Library Electronic Table of Contents (United Kingdom)

Global supply chain practices and their effects have received considerable attention over the last two decades. In the recent past, the need for integration across supply chains has been identified as a key for effective and efficient operations of supply chains. This is observed with the increasing trend of collaborative partnerships among supply chain partners. This paper presents an integrated approach for manufacturing and distribution networks within the supply chain system of a global car company. The paper shows that the integration of manufacturing and distribution networks creates the environment for effective planning of many components and execution/follow-up of those plans. These components include materials, resources, operations/activities, suppliers and customers. The main f...

Energy Technology Data Exchange (ETDEWEB)

In this paper, the question of whether the new distribution system for the electricity supply industry can deliver a better service to customers, is discussed. In particular it discusses the requirement of customers for low cost and efficiency, with particular reference to Victoria in general and Solaris in particular. Solaris comprises the amalgamation of five ex-Municipal Electricity Undertakings and one distribution part of the former State Electricity Commission. Despite not having a set of objectives, a strategy, a common culture, appropriate processes or systems, key account management skills, marketing and customer service expertise, commercial financial expertise, commercial treasury expertise and strategic skill, it has been able to develop a business plan and strategy to satisfy the shareholder (the government), improve customer communication facilities, set up human resource management mechanisms and liaison with ...

British Library Electronic Table of Contents (United Kingdom)

Until recently, the wavelength-division-multiplexed (WDM) transmission system has reached record capacities and distances due to innovations such as FEC (Forward Error Correction), distributed Raman amplification, new transmission fiber and advanced optical format. Optical-communication systems exclusively employed conventional On-Off Keying signals in either Non-Return-To-Zero (NRZ) or Return-To-Zero (RZ) format. Recently a number of advanced modulation formats have attracted attention. Some of these formats carry information through On-Off-Keying but also modulate the optical phase in order to enhance the robustness of signal to chromatic dispersion, optical filtering and non-linearities. Through extensive sets of simulation results, we showed that it is possible to replace a channel wit...

Energy Technology Data Exchange (ETDEWEB)

Nickel is present in radioactive waste (as activation products {sup 59}Ni and {sup 63}Ni) besides being an element widely distributed in the geosphere and considered for alloys in the engineered barrier systems for underground repositories. For these reasons, within the scope of the OECD Nuclear Energy Agency (NEA) Thermochemical Data Base (TDB) Project a comprehensive review of thermodynamic data has been carried out by the present authors [1]. Over 700 original bibliography sources have been considered, resulting in recommended data for over 50 inorganic species and compounds. Central to the new database are the selections for {delta}{sub f}G{sub m}{sup 0}(Ni{sup 2+}, 298.15 K), established on the basis of re-evaluations of potentiometric data for Ni{sup 2+} | Ni (cr) and S{sub m}{sup 0}(Ni{sup 2+}, 298.15 K) established on the dissolution equilibria for NiSO{sub 4}.7H{sub 2}O(cr). The resulting value for {delta}{sub f}H{sub m}{sup 0}(Ni{sup ...

Energy Technology Data Exchange (ETDEWEB)

In FY-2000, Engineering at Lawrence Livermore National Laboratory faced significant pressures to meet critical project milestones, and immediate demands to facilitate the reassignment of employees as the National Ignition Facility (the 600-TW laser facility being designed and built at Livermore, and one of the largest R&D construction projects in the world) was in the process of re-baselining its plan while executing full-speed its technology development efforts. This drive for change occurred as an unprecedented level of management and program changes were occurring within LLNL. I am pleased to report that we met many key milestones and achieved numerous technological breakthroughs. This report summarizes our efforts to perform feasibility and reduce-to-practice studies, demonstrations, and/or techniques--as structured through our technology centers. Whether using computational engineering to predict how giant structures like suspension bridges will ...

British Library Electronic Table of Contents (United Kingdom)

This work describes how a general, process-based mass-balance model (CoastMab) for phosphorus for coastal areas may be used as a tool to estimate realistic values of "natural" or preindustrial reference levels of key bioindicators in coastal science, including the Secchi depth, a standard measure of water clarity, the chlorophyll-a concentration, an operational measure of phytoplankton biomass and the concentration of cyanobacteria, a measure of the concentration of harmful algae. The CoastMab-model is an ecosystem model giving monthly predictions to achieve seasonal variations of basin-wide properties. The selected case-study area, the Gulf of Riga, is sensitive to nutrient loading because of its shallowness and low openness towards the Baltic Proper. The morphometry of any coastal area, ...

Energy Technology Data Exchange (ETDEWEB)

Substantial changes in the radial distribution function of amorphous Si films have been observed in neutron-diffraction studies. The spectra indicate changes in short-range order associated with an approx.11% modification in the bond-angle distribution width. The results allow the first direct comparison of structural and vibrational Raman probes of variations in local order in thin-film amorphous solids. Good agreement is obtained between the measured bond-angle variation and that based on Raman estimates.

Science.gov (United States)

The phase space beam analyzer is a measurement instrument that is applied in laser technology to perform analyses of the spatial and angular distribution of rays. We are interested in this instrument as a means to characterize non-coherent light sources. In this context, a closer look at the tolerances of this optical instrument was considered useful. Having a so-called quadrupole lens as a key element, the phase space beam analyzer is a device that features anamorphic optical properties. To describe these anamorphic properties, recurrence was made to a description by extended ray-transfer matrices. This formalism allows for an analysis of the alignment tolerances of the phase space beam analyzer and facilitates a study of the sensitivities of the instrument. The analysis is complemented using numerical ray tracing.

International Nuclear Information System (INIS)

High-energy ionizing radiation is a prominent modality for the treatment of many cancers. The approaches to electron dose calculation can be categorized into semi-empirical models (e.g. Fermi-Eyges, convolution-superposition) and probabilistic methods (e.g. Monte Carlo). A third approach to dose calculation has only recently attracted attention in the medical physics community. This approach is based on the deterministic kinetic equations of radiative transfer. We derive a macroscopic partial differential equation model for electron transport in tissue. This model involves an angular closure in the phase space. It is exact for the free streaming and the isotropic regime. We solve it numerically by a newly developed HLLC scheme based on Berthon et al (2007 J. Sci. Comput. 31 347-89) that exactly preserves the key properties of the analytical solution on the discrete level. We discuss several test cases taken from the medical ...

British Library Electronic Table of Contents (United Kingdom)

The impacts of the availability of low-carbon technologies on the regional distribution of mitigation costs are analyzed in a global multi-regional integrated assessment model. Three effects on regional consumption losses are distinguished: domestic measures, trade of fossil energy carriers and trade of emission permits. Key results are: (i) GDP losses and a redirection of investments in the energy system towards capital-intensive technologies are major contributions to regional consumption losses. (ii) A devaluation of tradable fossil energy endowments contributes largely to the mitigation costs of fossil fuel exporters. (iii) In case of reduced availability of low-carbon technologies, the permit market volume and associated monetary redistributions increase. The results suggest that the ...

International Nuclear Information System (INIS)

The proactive protection measures and the traditional passive security protection tools are complementarities each other. It also can supply the conventional network security protection system and enhance its capability of the security protection. Based upon sorts of existing network security technologies, this article analyses and summarizes the technologies, functions and the development directions of some key proactive network security protection tools. (authors)

British Library Electronic Table of Contents (United Kingdom)

Abstract Gelatinization temperature (GT) is an important parameter in evaluating the cooking and eating quality of rice. Indeed, the phenotype, biochemistry and inheritance of GT have been widely studied in recent times. Previous map-based cloning revealed that GT was controlled by ALK gene, which encodes a putative soluble starch synthase II-3. Complementation vector and RNAi vector were constructed and transformed into Nipponbare mediated by Agrobacterium. Phenotypic and molecular analyses of transgenic lines provided direct evidence for ALK as a key gene for GT. Meanwhile, amylose content, gel consistency and pasting properties were also affected in transgenic lines. Two of four nonsynonymous single nucleotide polymorphisms in coding sequence of ALK were identified as essential for GT. ...

Energy Technology Data Exchange (ETDEWEB)

Microcomputers are beginning to be used for energy analysis in many developing countries, and have the potential for making a significant contribution to the resolution of difficult analytical and data problems, and to improving communications between analyst and decision maker. Successful introduction of a microcomputer based on analytical capability, however, requires attention to several important factors in order to avoid the mistakes of the earlier mainframe computer era. This paper reviews the key issues of matching models to staff capabilities, of training, and of the operating environment, based on the author's first-hand experience with microcomputer projects in Uruguay, Haiti and Sri Lanka. 3 figures, 3 tables.

Energy Technology Data Exchange (ETDEWEB)

Optimal capacitor placement determines the size, type, and location of capacitors to be installed on a radial distribution feeder that will reduce peak power and energy losses while minimizing the costs of investment and installation of the capacitor banks. This paper describes a sensitivity-based optimal placement of capacitors that employs a new load characterization scheme using a voltage-current-angle-logger. The proposed method allows modeling of loads of different power factors for different portions of the distribution feeder. The optimal solution is obtained by testing various combinations of capacitor banks (based on the smallest bank size specified by the user) and candidate nodes along the distribution feeder, and calculating the resultant savings. In order to reduce solution time, the candidate nodes are ranked according to their sensitivity factors. The highest ranking ...

Energy Technology Data Exchange (ETDEWEB)

The distribution of the alkaline earth elements strontium and barium between the solid phases of phosphates of transition elements of group 4 and chloride melts was studied. The distribution coefficients of strontium and barium were found at T = 700-800/sup 0/C. Phosphates of the type NaM/sub 2//sup (IV)/(PO/sub 4/)/sub 3/, where M/sub (IV)/ represents titanium, zirconium, and hafnium, were used as the solid phases. It was established that there is an enrichment of the precipitates with the distributed components. The distribution coefficient depends on the nature of the solid phase and the temperature. It was suggested that M/sup (II)/ x M/sub 4//sup (IV)/(PO/sub 4/)/sub 6/ is formed in processes of distribution, where M/sup (II)/ represents Sr, Ba.

British Library Electronic Table of Contents (United Kingdom)

Research in the field of river hydrology has been mainly concerned with the investigation of the rainfall-runoff phenomenon through the analysis of hydrological factors such as meteorology and geography, with the focus being on each river basin. Recently, various forms of digital information such as GIS (Geographic Information System) and RS (Remote Sensing) data have been made available in worldwide digital map format. Therefore, there has been a shift in focus from lumped-parameter models to distributed runoff models, as the latter can consider temporal and spatial variations in water quantity. Distributed runoff models have made possible the comparison of runoff field and rainfall-runoff characteristics considering spatial distribution. Hydrological conditions are differently distribute...

International Nuclear Information System (INIS)

A ground-breaking study was recently completed as part of the Seabrook Level 2 PRA update. This study updates the post-core damage phenomena to be consistent with the most recent information and includes accident management activities that should be modeled in the Level 2 PRA. Overall, the result is a Level 2 PRA that fully meets the requirements of the ASME PRA Standard with respect to modeling accident management in the LERF assessment and NRC requirements in Regulatory Guide 1.174 for considering late containment failures. This technical paper deals only with the incorporation of operator actions into the Level 2 PRA based on a comprehensive study of the Seabrook Station accident response procedures and guidance. The paper describes the process used to identify the key operator actions that can influence the Level 2 PRA results and the development of success criteria for these key operator actions. This addresses a ...

International Nuclear Information System (INIS)

We present an abundance analysis based on high-resolution spectra of 10 stars selected to span the full range in metallicity in the Ursa Minor (UMi) dwarf spheroidal (dSph) galaxy. We find that [Fe/H] for the sample stars ranges from -1.35 to -3.10 dex. Combining our sample with previously published work for a total of 16 luminous UMi giants, we establish the trends of abundance ratios [X/Fe] as functions of [Fe/H] for 15 elements. In key cases, particularly for the #alpha#-elements, these trends resemble those for stars in the outer part of the Galactic halo, especially at the lowest metallicities probed. The neutron-capture elements show an r-process distribution over the full range of Fe metallicity reached in this dSph galaxy. This suggests that the duration of star formation in the UMi dSph was shorter than in other dSph galaxies. The derived ages for a larger sample of UMi stars with more uncertain metallicities also ...

Energy Technology Data Exchange (ETDEWEB)

Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires determination of the effective thermal conductivity as well as the thermal contact resistance associated with the interface between the GDL and adjacent surfaces/layers. In the present study, a custom-made test bed that allows the separation of effective thermal conductivity and thermal contact resistance in GDLs under vacuum and ambient conditions is described. Measurements under varying compressive loads are performed using Toray carbon paper samples with a porosity of 78% for a range of thicknesses. The measurements are complemented by compact analytical models that achieve good agreement with experimental data. A key finding is that thermal contact resistance is the dominant component of the total thermal resistance; neglecting this phenomenon may result in significant errors in ...

Energy Technology Data Exchange (ETDEWEB)

Using the Philips DRM distributed real-time multiprocessing system, designers can implement high-performance computer systems using VME hardware and the C programming language. The system provides a virtual-processing environment in which several 68000 CPUs share the workload. There are no centralized components, and tasks can be assumed by the rest of a system in the event of an individual processor's failure.

UK PubMed Central (United Kingdom)

BackgroundThere are 146 million underweight children in the developing world, which contribute to up to half of the world's child deaths. In high burden regions for malnutrition,...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

This paper introduces a parallel measurement approach for fast infrared-based human temperature screening suitable for use in a large public area. Our key idea is based on the combination of simple image processing algorithms, infrared technology, and human flow management. With this multidisciplinary concept, we arrange as many people as possible in a two-dimensional space in front of a thermal imaging camera and then highlight all human facial areas through simple image filtering, image morphological, and particle analysis processes. In this way, an individual's face in live thermal image can be located and the maximum facial skin temperature can be monitored and displayed. Our experiment shows a measured 1ms processing time in highlighting all human face areas. With a thermal imaging ca...

Energy Technology Data Exchange (ETDEWEB)

Metals for potential use in the dissociator and the synthesizer reactors of a distributed solar receiver thermochemical transport loop utilizing SO/sub 3//SO/sub 2//O/sub 2/ molecular chemistry were tested in SO/sub 2//O/sub 2/ mixtures at 500/sup 0/C and 900/sup 0/C, respectively, for times of up to four weeks. They included titanium, aluminum and nickel, and iron-base, nickel-base and cobalt-base superalloys. Weight gain measurements determine the oxidation/sulfidation kinetics. Electron microprobe analysis identifies any possible penetration of oxygen and sulfur into the metal and the formation of internal oxides and sulfides. The most promising candidates as a result of these tests are the cobalt-base superalloys.

CERN Document Server

Sparse learning has recently received increasing attention in many areas including machine learning, statistics, and applied mathematics. The mixed-norm regularization based on the L1/Lq norm with q > 1 is attractive in many applications of regression and classification in that it facilitates group sparsity in the model. The resulting optimization problem is, however, challenging to solve due to the structure of the L1/Lq -regularization. Existing work deals with special cases including q = 2,infinity, and they cannot be easily extended to the general case. In this paper, we propose an efficient algorithm based on the accelerated gradient method for solving the L1/Lq -regularized problem, which is applicable for all values of q larger than 1, thus significantly extending existing work. One key building block of the proposed algorithm is the L1/Lq -regularized Euclidean projection (EP1q). Our theoretical analysis reveals ...

CERN Document Server

Effect of a planar texture quality and its thickness on lasing spectrums and thresholds in dye-doped cholesteric liquid crystal (CLC) of steroid type is explored. Transition from the qualitative planar texture to the poor texture quality is accompanied by change of characteristic mode structures and by shift of barycentre in the long-wave side and the considerable growth of the lasing threshold. It is found that in the CLC texture created by substrates with perpendicular directions of orientation the stable single-mode lasing takes place. The nature of oscillated modes in such texture is caused by phase jump. The gained results show that in steroid CLC, unlike induced one, lasing spectrums is possible to feature with the coupled wave model. Key words: steroidal cholesteric liquid crystal, distributed feedback lasing, oscillation thresholds, phase defect of periodical structure, transmission and lasing spectra

Energy Technology Data Exchange (ETDEWEB)

This experimental research investigates mixed convection and heat transfer augmentation by gaseous forced jets in a large enclosure, at conditions simulating those of passive containment cooling systems for Gen III+ passively safe reactors. The experiment is designed to measure the key parameters governing heat transfer augmentation by forced jets, and to investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio. The tests cover a variety of injection modes leading to flow configurations of interest for mixing and stratification phenomena in containments under accident conditions. Correlations for heat transfer augmentation by forced jets are developed and compared with experimental data. The characteristic recirculation speed inside the enclosure is introduced and analyzed. Steady stratified temperature distributions are compared with model simulations ...

Science.gov (United States)

Generalized linear models (GLMs), as defined by J. A. Nelder and R. W. M. Wedderburn (1972), unify a class of regression models for categorical, discrete, and continuous response variables. As an extension of classical linear models, GLMs provide a common body of theory and methodology for some seemingly unrelated models and procedures, such as the logistic, Poisson, and probit models, that are increasingly used in family studies. This article provides an overview of the principle and the key components of GLMs, such as the exponential family of distributions, the linear predictor, and the link function. To illustrate the application of GLMs, this article uses Canadian national survey data to build an example focusing on the number of close friends among older adults. The article concludes with a discussion of the strengths and weaknesses of GLMs.

British Library Electronic Table of Contents (United Kingdom)

Mapping the distribution of invasive alien plant species is significant for testing ecological hypotheses and for guiding effective management. Little is known about the distribution of invasive plants at landscape scale, and the factors controlling their dispersal and establishment are still poorly understood. This is the case for Rosa rugosa, an invasive shrub with negative effects on biodiversity in dune ecosystems of NW Europe. The aim of the study was to identify the factors which determine the distribution of R. rugosa in coastal dunes. In a large semi-natural dune area of NW Denmark (2364ha) all patches of the species (1321, 1.3-59.1m2) were GPS mapped. Patch distribution was GIS analysed, based on aerial photographs and vegetation maps. The distance of R. rugosa from the most consp...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to extend the knowledge base for wetland treatment to include processes and substances of particular importance to small, on-site systems receiving oil and gas well waste water. Collection of data on the sorption of heavy metals and the degradation of toxic organics is one of the key tasks. The toxic organics phenolics and anthracene, and chromium and copper have been selected as target adsorbates. An information search was performed on oil refinery waste treatment wetland systems.

British Library Electronic Table of Contents (United Kingdom)

Purpose - This paper seeks to analyse the hypothesis that sustainability is destined to become the operating paradigm for construction education in the UK. Design/methodology/approach - An international literature review is used to assess the relationship between sustainability and the built environment. The viewpoints of the construction-related professions are examined by analysing the accreditation policies of key professional bodies and through a survey of public sector-based UK building professionals. International and national policy initiatives on educating for sustainability are reviewed and a survey of UK universities delivering construction degrees is used to explore the environmental content of construction courses. A brief case study describes recent efforts to systematically e...

Energy Technology Data Exchange (ETDEWEB)

Disaster impact modeling and analysis uses huge volumes of image data that are produced immediately following a natural or an anthropogenic disaster event. Rapid damage assessment is the key to time critical decision support in disaster management to better utilize available response resources and accelerate recovery and relief efforts. But exploiting huge volumes of high resolution image data for identifying damaged areas with robust consistency in near real time is a challenging task. In this paper, we present an automated image analysis technique to identify areas of structural damage from high resolution optical satellite data using features based on image content.

International Nuclear Information System (INIS)

We study a quantum computing system using microwave photons in transmission line resonators on a superconducting chip as qubits. We show that linear optics and other controls necessary for quantum computing can be implemented by coupling to Josephson devices on the same chip. By taking advantage of the strong nonlinearities in Josephson junctions, photonic qubit interactions can be realized. We analyze the gate error rate to demonstrate that our scheme is realistic even for Josephson devices with limited decoherence times. As a conceptually innovative solution based on existing technologies, our scheme provides an integrated and scalable approach to the next key milestone for photonic qubit quantum computing.

Science.gov (United States)

This paper focuses on a theoretical model that predicts the temperature increase of Magneto-rheological (MR) fluid dampers experiencing a sinusoidal input motion. A theoretical model is developed to estimate the temperature rise based on the non-linear behavior of the MR fluid damper. This model is solved numerically, and the numerical solution is compared with a known linear solution and experimental result in order to validate the accuracy of the model. Also, a non-dimensional form of the governing equations are developed to examine the key parameters. The non-dimensional terms show the effect of external and internal parameters on the trends of heat dissipation as well as heat generation within the MR fluid damper.

British Library Electronic Table of Contents (United Kingdom)

Italian district small and medium enterprises (SMEs) developed aggressive strategies to extend their sales networks and supply chains abroad. Literature on districts offered alternative explanations about the impacts of internationalization on local manufacturing systems. The authors consider the evolution of Italian districts in the framework of global value chain approach, focusing on the role of leading firms. Based on a survey of 650 Italian SMEs and financial indicators, the paper describes the rise of a new district firm model, the open network, which becomes a key node of global value chains. The paper also analyses the relationships among internationalization, innovation strategies and performance of SMEs.

International Nuclear Information System (INIS)

The process of miniemulsification allows the generation of small, homogeneous, and stable droplets containing monomer or polymer precursors and magnetite which are then transferred by polymer reactions to the final polymer latexes, keeping their particular identity without serious exchange kinetics involved. It is shown that the miniemulsion process can excellently be used for the formulation of polymer-coated magnetic nanoparticles which can further be used for biomedical applications. The use of high shear, appropriate surfactants, and the addition of a hydrophobe in order to suppress the influence of Ostwald ripening are key factors for the formation of the small and stable droplets in miniemulsion and will be discussed. Two different approaches based on miniemulsion processes for the encapsulation of magnetite into polymer particles will be presented in detail.

British Library Electronic Table of Contents (United Kingdom)

Based on the Morlet wavelet transformation and Wigner-Ville distribution (WVD), we present a wind turbine fault diagnosis method in this paper. Wind turbine can be damaged by moisture absorption, fatigue, wind gusts or lightening strikes. Due to this reason, there is an increasing need to monitor the health of these structures. Vibration analysis is the best-known technology applied in wind turbine condition monitoring, in which the time-frequency analysis techniques such as Wigner-Ville distribution (WVD) are widely used. Theoretically WVD has an infinite resolution in time-frequency domain. For early wind turbine fault signals, however, there are two main difficulties in WVD analysis. One is strong noise signals in the background and the other is cross terms in WVD itself. In this paper,...

Energy Technology Data Exchange (ETDEWEB)

The task of designing high performance X-ray optical systemsrequires the development of sophisticated X-ray scattering calculationsbased on rigorous information about the optics. One of the mostinsightful approaches to these calculations is based on the powerspectral density (PSD) distribution of the surface height. The majorproblem of measurement of a PSD distribution with an interferometricand/or atomic force microscope arises due to the unknown ModulationTransfer Function (MTF) of the instruments. The MTF characterizes theperturbation of the PSD distribution at higher spatial frequencies. Here,we describe a new method and dedicated test surfaces for calibration ofthe MTF of a microscope. The method is based on use of a speciallydesigned Binary Pseudo-random (BPR) grating. Comparison of atheoretically calculated PSD spectrum of a BPR grating with a spectrummeasured with the ...

British Library Electronic Table of Contents (United Kingdom)

To improve the performance of voice activity detector (VAD) in noisy environments, this paper concentrates on three critical aspects related to noise robustness including speech features, feature distributions and temporal dependence. Based on the statistic on TIMIT and NOIZEUS, Mel-frequency cepstrum coefficients (MFCCs) are selected as speech features, Gaussian Mixture distributions (GMD) are applied to associate the observations in MFCC domain with both speech and non-speech states, and Weibull and Gamma distributions are used to explicitly model noise and speech durations, respectively. To integrate these aspects into VAD, the hidden semi-Markov model (HSMM) as a generalized hidden Markov model (HMM) is introduced first. Then the VAD decision is made according to the likelihood ratio t...

International Nuclear Information System (INIS)

This work improves the reliability and accuracy in the reconstruction of the total isotope activity content in heterogeneous nuclear waste drums containing point sources. The method is based on #chi#"2-fits of the angular dependent count rate distribution measured during a drum rotation in segmented gamma scanning. A new description of the analytical calculation of the angular count rate distribution is introduced based on a more precise model of the collimated detector. The new description is validated and compared to the old description using MCNP5 simulations of angular dependent count rate distributions of Co-60 and Cs-137 point sources. It is shown that the new model describes the angular dependent count rate distribution significantly more accurate compared to the old model. Hence, the reconstruction of the activity is more accurate and the errors are ...

Energy Technology Data Exchange (ETDEWEB)

The report presents a long-range plan for a broad-based, coordinated research, development and market transformation program for reducing the lighting energy intensities in commercial and residential buildings in California without compromising lighting quality. An effective program to advance lighting energy efficiency in California must be based on an understanding that lighting is a mature field and the lighting industry has developed many specialized products that meet a wide variety of light needs for different building types. Above all else, the lighting field is diverse and there are applications for a wide range of lighting products, systems, and strategies. Given the range of existing lighting solutions, an effective energy efficient lighting research portfolio must be broad-based and diverse to match the diversity of the lighting market itself. The belief that there is one solution--a magic bullet, such as a ...

International Nuclear Information System (INIS)

An important unresolved issue in outcomes analysis for lung complications is the effect of poor or completely lacking heterogeneity corrections in previously archived treatment plans. To estimate this effect, we developed a novel method based on Monte Carlo (MC) dose calculations which can be applied retrospectively to RTOG/AAPM-style archived treatment plans (ATP). We applied this method to 218 archived nonsmall cell lung cancer lung treatment plans that were originally calculated either without heterogeneity corrections or with primitive corrections. To retrospectively specify beam weights and wedges, beams were broken into Monte Carlo-generated beamlets, simulated using the VMC++ code, and mathematical optimization was used to match the archived water-based dose distributions. The derived beam weights (and any wedge effects) were then applied to Monte Carlo beamlets regenerated based on the patient ...

Science.gov (United States)

A doubly Q-switched laser with both an acousto-optic (AO) modulator and a GaAs saturable absorber can obtain a more symmetric and shorter pulse with high pulse peak power, which has been experimentally proved. The key parameters of an optimally coupled doubly Q-switched laser with both an AO modulator and a GaAs saturable absorber are determined, and a group of general curves are generated for what we believe is the first time, when the single-photon absorption (SPA) and two-photon absorption (TPA) processes of GaAs are combined, and the Gaussian spatial distributions of the intracavity photon density and the initial population-inversion density as well as the influence of the AO Q-switch are considered. These key parameters include the optimal normalized coupling parameter, the optimal normalized GaAs saturable absorber parameters, and the normalized parameters of the AO Q-switch, which can maximize the output energy. ...

International Nuclear Information System (INIS)

Neutron and gamma ray energy spectra were measured using an NE-213 scintillator at depths of 7.2, 15.2, and 22.2 cm in a tissue-equivalent phantom which was uniformly irradiated on one face by deuterium--tritium (DT) neutrons. Coupled neutron--gamma ray multigroup discrete-ordinates calculations were performed using semi-infinite slab geometry. These calculations were used to supplement the measured spectra below 1 MeV. Similar calculations were performed to study the perturbation in the phantom due to the detector. The measured and calculated spectra were used to determine the kerma distributions for neutrons and gamma rays at each location. The gamma radiation was determined to contribute more than 10% of the total dose at each depth. The calculated kerma also reveals that a knowledge of the gamma ray spectra below 1 MeV is desirable. Key words: neutron--gamma spectra, spectrometry, kerma distributions, coupled multigroup ...

CERN Document Server

Anti-proton and positron Galactic cosmic ray (GCR) spectra are among the key targets for indirect detection of dark matter (DM). The boost factors, corresponding to an enhancement of the signal|linked to the clumpiness properties of the dark matter distribution|, have been taken as high as thousands in the past. The dramatic impact of these boost factors for indirect detection of antiparticles, for instance with the PAMELA satellite or the coming AMS-02 experiment, asks for their detailed calculation. We take into account the state-of-the-art results of high resolution N-body dark matter simulations to calculate the most likely energy dependent boost factors|linked to the GCR propagation properties|, for anti-protons and positrons. The results from extreme, but still possible, configurations of the clumpy dark matter component is also discussed. Starting from the mass and space distributions of sub-halos, the anti-proton ...

International Nuclear Information System (INIS)

CANDU 600 nuclear reactors are usually fuelled with STANDARD (STD), 37 rods fuel bundles. Natural uranium (NU) dioxide (UO_2), is used as fuel composition. A new fuel bundle geometry called CANFLEX (CFX) with 43 rods is proposed and some new fuel composition are considered. Flexibility is the key word for the attempt to use some different fuel geometries and compositions for CANDU 600 nuclear reactors as well as for innovative ACR-700/1000 nuclear reactors. The fuel bundle considered in this paper is CFX-RU-0.90 that encodes the CANFLEX geometry, recycled dioxide uranium (RU) with 0.90% enrichment. The goal of this proposal is ambitious: a higher average discharge burn-up up to 14000 MWd/tU and, for the same amount of generated electric power, reduction in nuclear fuel fabrication, reduction of spent nuclear fuel radioactive waste and reduction of refueling operational work by using fewer bundles. An improved sub-channel approach for thermal-hydraulic analysis is ...

Energy Technology Data Exchange (ETDEWEB)

In the area of seasonally thawing soil, porous or broken coatings cannot significantly retard the process of pile metal destruction, since it will occur through electroosmotic penetration of the base electrolyte to the metal surface. Such processes can be prevented by electrochemical protective methods. Systems based on grid cathode stations with power control and distribution units are recommended for use for cathode protection of steel pile foundations.

Energy Technology Data Exchange (ETDEWEB)

This contribution is an informal essay based on a talk delivered at the Institute for Mathematics and its Applications (IMA) in Minneapolis, under the summer program in molecular biology, July 18-22, 1994. I exclude many technical details, which can be found elsewhere, and instead focus on the basic ideas of molecular dynamics simulations, with the goal of conveying to students and non-specialists the key concepts of the theory and practice of large-scale simulations. Following a description of the basic idea in molecular dynamics, I discuss some of the practical details involved in simulations of large biological molecules, the numerical timestep problem, and approaches to this problem based on implicit-integration techniques. I end with a perspective of open challenges in the field and directions for future research. 79 refs., 6 figs., 1 tab.

CERN Document Server

This paper presents three non-linear asymptotic observers corresponding to three examples of engineering interest: a chemical reactor, a non-holonomic car, and an inertial navigation system. For each example, the design is based on physical symmetries. This motivates the theoretical development of invariant observers, i.e, symmetry-preserving observers. We consider an observer to consist in a copy of the system equation and a correction term, and we give a constructive method (based on the Cartan moving-frame method) to find all the symmetry-preserving correction terms. They rely on an invariant frame (a classical notion) and on an invariant output-error, a less standard notion precisely defined here. For each example, the convergence analysis relies also on symmetries consideration with a key use of invariant state-errors. For the non-holonomic car and the inertial navigation system, the invariant state-errors is shown to ...

British Library Electronic Table of Contents (United Kingdom)

Due to recent advancements in mobile computing and communication technologies, mobile ad hoc computational Grids are emerging as a new computing paradigm, enabling innovative applications through sharing of computing resources among mobile devices without any pre-existing network infrastructure. Energy-efficient resource allocation is one of the key issues in mobile ad hoc computational Grids due to limited battery life of mobile nodes. To reduce energy consumption, we propose a hybrid power-based resource allocation scheme for allocation of interdependent tasks to nodes within mobile ad hoc computational Grid. The basic idea is to exploit dependencies and task type, and allocate interdependent tasks to nodes accessible at minimum transmission power. We also propose a power-based algorithm...

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Wireless mesh networks can provide low-cost solutions for extending the reach of wireless access points by using multi-hop routing over a set of stationary wireless routers. The routing protocol for these networks may need to address quality considerations to meet the requirements of the user. In this paper, we present a quality based routing protocol for wireless mesh networks that tries to maximize the probability of successful transmissions while minimizing the end-to-end delay. The proposed routing protocol uses reactive route discoveries to collect key parameters from candidate routes to estimate the probability of success and delay of data packets transmitted over them. To achieve accurate route quality assessments, a new route quality metric is proposed that uses performance models ...

British Library Electronic Table of Contents (United Kingdom)

In this paper, a hybrid time-frequency method (HTM) based on the improved Morlet wavelet and auto terms window (ATW) is presented. The Morlet wavelet, for its shape is similar to the mechanical shock signals, is added two parameters which decide the shape of the mother wavelet. The added parameters and the appropriate scale parameter for continuous wavelet transformation (CWT) are calculated using the cross validation method (CVM) and the minimum Shannon entropy method. The useless noise in the original signal can be filtered by the CWT filter de-noising process. An ATW based on the Smoothed Pseudo Wigner-Ville Distribution (SPWVD) spectrum is designed as a window function to suppress the cross terms in Wigner-Ville Distribution (WVD). The gear fault diagnosis experiment results show that ...

Energy Technology Data Exchange (ETDEWEB)

In nuclear fuel, in approximately one quarter of the fissions, one of the two formed fission products is gaseous. These are mainly the noble gases xenon and krypton with isotopes of xenon contributing up to 90% of the product gases. These noble fission gases do not combine with other species, and have a low solubility in the normally used uranium oxide matrix. They can be dissolved in the fuel matrix or precipitate in nanometer-sized bubbles within the fuel grain, in micrometer-sized bubbles at the grain boundaries, and a fraction also precipitates in fuel pores, coming from fuel fabrication. A fraction of the gas can also be released into the plenum of the fuel rod. With increasing fission, and therefore burn-up, the ceramic fuel material experiences a transformation of its structure in the 'cooler' rim region of the fuel. A subdivision occurs of the original fuel grains of few microns size into thousands of small grains of sub-micron sizes. Additionally, larger ...

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The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOVA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan ...

Energy Technology Data Exchange (ETDEWEB)

The study of natural convection flow and heat transfer within a cylindrical annulus has received considerable attention because of its numerous applications, such as in nuclear reactor design, electronic component cooling, thermal storage systems, energy conservation, energy storage, and energy transmission. Here, the effects of multiple geometric perturbations on the inner and outer cylinders of an annulus with impermeable end walls are investigated in this work. A three-dimensional study was done using a numerical scheme based on a Galerkin method of finite element formulation. The nature of the buoyancy-induced flow field has been analyzed in detail. The flow fields for the cases considered were found to be qualitatively similar, and the introduction of each additional perturbation altered the flow field in a regular and recurring manner. The introduction of each perturbation on the outer cylinder causes clockwise and counterclock-wise rotating patterns on ...

Science.gov (United States)

In an era of unprecedented technological advancement and economic expansion, construction practice continues to evolve but construction education has not changed appreciably since the 1990s. This schism has prompted industry, government, and other key constituents to question the relevancy and efficacy of current programs. The Accreditation Board for Engineering and Technology (ABET) Engineering Criteria 2000 and the American Council for Construction Education (ACCE) emphasizes outcomes over process, and provides an opportunity for stakeholders to help universities define educational goals and objectives and design a curriculum to meet the desired outcomes. While the need for curriculum modification has been acknowledged, the industry position was amorphous and anecdotal and therefore difficult to address. Qualitative methodologies such as formal surveys and structured interviews can be used to capture and quantify industry expectations of the needed attributes ...

International Nuclear Information System (INIS)

Dose reconstruction is a process that re-creates the treatment-time dose deposited in a patient provided there is knowledge of the delivered energy fluence and the patient's anatomy at the time of treatment. A method for reconstructing dose is presented. The process starts with delivery verification, in which the incident energy fluence from a treatment is computed using the exit detector signal and a transfer matrix to convert the detector signal to energy fluence. With the verified energy fluence and a CT image of the patient in the treatment position, the treatment-time dose distribution is computed using any model-based algorithm such as convolution/superposition or Monte Carlo. The accuracy of dose reconstruction and the ability of the process to reveal delivery errors are presented. Regarding accuracy, a reconstructed dose distribution was compared with a measured film distribution for a simulated ...

International Nuclear Information System (INIS)

Differential cross sections of elastic scattering of 104 MeV #alpha# particles from "2"0"4,"2"0"6,"2"0"8Pb have been measured with high angular accuracy. The analyses are based on a folding model treating the proton and neutron distributions independently. The proton distributions were taken from precise electron scattering results. The neutron distributions were parametrized by a modified Gaussian the parametrers of which were varied in order to fit the experimental cross sections. The resulting rms radii of the neutron distributions exceed the rms radii of the proton distributions by #DELTA#r=0.22 +- 0.09 fm for "2"0"4Pb, #DELTA#r = 0.19 +- 0.09 fm for "2"0"6Pb, and #DELTA#r = 0.30 +- 0.07 fm for "2"0"8Pb.

International Nuclear Information System (INIS)

A ''coherent flucton'' nuclear model is proposed which provides for new possibilities for particle scattering studies on nuclei. It is based on the data of nuclear matter density distribution and is used for calculating the ground state energy of Fermi system terminals. The ''coherent flucton'' model is applied to the distribution of 1 GeV protons on "2"8Si, "3"2S, "4"0Ca, "4"8Ca, "5"8Ni, "2"0"8Pb nuclei. The calculations by the model agree well with experimental data.

Science.gov (United States)

The entrainment flow rate distribution, the gas velocity profile, and the concentration profile of droplets across the channel cross section in fully developed region of a horizontal rectangular channel of 150mm width and 50mm height were measured. The concentration profile of droplets was expressed by a simple equation based on a constant diffusion coefficient model. From this equation the effects of gravity and turbulent diffusion of droplets on the concentration profile were evaluated. The characteristic mean settling velocity of a group of droplets with various diameters was derived, and using this value the mean diffusion coefficient of the group of droplets was obtained

Energy Technology Data Exchange (ETDEWEB)

When searching for anisotropies in the arrival directions of Ultra High Energy Cosmic Rays, one must estimate the number of events expected in each direction of the sky in the case of a perfect isotropy. We present in this article a new method, developed for the Auger Observatory, based on a smooth estimate of the zenith angle distribution obtained from the data itself (which is essentially unchanged in the case of the presence of a large scale anisotropy pattern). We also study the sensitivity of several methods to detect large-scale anisotropies in the cosmic ray arrival direction distribution : Rayleigh analysis, dipole fitting and angular power spectrum estimation.

Energy Technology Data Exchange (ETDEWEB)

The present authors have previously developed a new method for Probabilistic Fracture Mechanics (PFM), which they call Recursive Distribution (RD) method. The method is based on the construction of the Lebesgue-Stieltjes measure through a deterministic mapping defining a crack growth process. In the present paper, its theoretical background is first discussed, and the Lebesgue decomposition of the measure is given. Then a numerical example of a Light Water Reactor (LWR)`s piping problem is solved by the present method, and the results are compared with those of the Monte Carlo (MC) method. In addition to leakage probability, a variation in stress cycles of the marginal distribution of an aspect ratio of a semi-elliptical surface crack is calculated, which will be used in a study on LBB evaluation.

CERN Document Server

In this work we investigate the multivariate statistical description of the matter distribution in the nonlinear regime. We introduce the multivariate Edgeworth expansion of the lognormal distribution to model the cosmological matter field. Such a technique could be useful to generate and reconstruct three-dimensional nonlinear cosmological density fields with the information of higher order correlation functions. We explicitly calculate the expansion up to third order in perturbation theory making use of the multivariate Hermite polynomials up to sixth order. The probability distribution function for the matter field includes at this level the two-point, the three-point and the four-point correlation functions. We use the hierarchical model to formulate the higher order correlation functions based on combinations of the two-point correlation function. This permits us to find compact expressions for the ...

British Library Electronic Table of Contents (United Kingdom)

In the parametric regression model, the covariate missing problem under missing at random is considered. It is often desirable to use flexible parametric or semiparametric models for the covariate distribution, which can reduce a potential misspecification problem. Recently, a completely nonparametric approach was developed by [H.Y. Chen, Nonparametric and semiparametric models for missing covariates in parameter regression, J. Amer. Statist. Assoc. 99 (2004), pp. 1176-1189; Z. Zhang and H.E. Rockette, On maximum likelihood estimation in parametric regression with missing covariates, J. Statist. Plann. Inference 47 (2005), pp. 206-223]. Although it does not require a model for the covariate distribution or the missing data mechanism, the proposed method assumes that the covariate distribut...

Energy Technology Data Exchange (ETDEWEB)

The task of designing high performance X-ray optical systems requires the development of sophisticated X-ray scattering calculations based on rigorous information about the optics. One of the most insightful approaches to these calculations is based on the power spectral density (PSD) distribution of the surface height. The major problem of measurement of a PSD distribution with an interferometric and/or atomic force microscope arises due to the unknown Modulation Transfer Function (MTF) of the instruments. The MTF characterizes the perturbation of the PSD distribution at higher spatial frequencies. Here, we describe a new method and dedicated test surfaces for calibration of the MTF of a microscope. The method is based on use of a specially designed Binary Pseudo-random (BPR) grating. Comparison of a theoretically calculated PSD spectrum of a BPR grating with a ...

Energy Technology Data Exchange (ETDEWEB)

The PIUS reactor utilizes simplified, inherent, passive, or other innovative means to accomplish safety functions. Accordingly, the PIUS reactor is subject to the requirements of 10CFR52.47(b)(2)(i)(A). This regulation requires that the applicant adequately demonstrate the performance of each safety feature, interdependent effects among the safety features, and a sufficient data base on the safety features of the design to assess the analytical tools used for safety analysis. Los Alamos has assessed the quality and completeness of the existing and planned data bases used by Asea Brown Boveri to validate its safety analysis codes and other relevant data bases. Only a limited data base of separate effect and integral tests exist at present. This data base is not adequate to fulfill the requirements of 10CFR52.47(b)(2)(i)(A). Asea Brown Boveri has stated that it plans to conduct more ...

International Nuclear Information System (INIS)

A nuclear power plant engineering (NPP) simulator may include many system functions such as thermal-hydraulic calculation, 3D reactor neutron kinetics model, control and protection system, display and operational human-machine interface, intelligent alarm system, etc. If all those functions are simulated using a single code, the size of the program will cause structural or managerial problems, and the hardware requirement could be tremendous. Thus, any local function errors or changes may affect the whole code, which will make development and maintenance extremely costly. So the nondistributed code is not considered to be flexible and feasible. Currently, distributed and parallel technologies have been applied to develop NPPs engineering simulator for safety analysis, verification of advanced main control room display, operation and intelligent alarm design. The distributed simulation divides a huge task into several objects according to ...

CERN Document Server

The paper considers software development issues for large-scale enterprise information systems (IS) with databases (DB) in global heterogeneous distributed computational environment. Due to high IT development rates, the present-day society has accumulated and rapidly increases an extremely huge data burden. Manipulating with such huge data arrays becomes an essential problem, particularly due to their global distribution, heterogeneous and weak-structured character. The conceptual approach to integrated Internet-based IS design, development and implementation is presented, including formal models, software development methodology and original software development tools for visual problem-oriented development and content management. IS implementation results proved shortening terms and reducing costs of implementation compared to commercial software available.

Science.gov (United States)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distribution of stable iodine tablets is advised. PMID:20332130

International Nuclear Information System (INIS)

The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of ...

International Nuclear Information System (INIS)

Findings indicate an urgent need to establish a monitoring program for persistent organic pollutants in water and sediment. - Marine culture is thriving in China and represents a major component of the regional economy in coastal zones, yet the environmental quality of many of those areas has never been studied. This paper attempts to investigate the quality status of Daya Bay, a key aquaculture area in China. The levels of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in water and sediment samples of the bay. The total concentrations of 16 PAHs varied from 4228 to 29325 ng l"-"1 in water, and from 115 to 1134 ng g"-"1 dry weight in sediments. In comparison to many other marine systems studied, the PAH levels in Daya Bay waters were relatively high, and at six sites they were sufficiently high (>10 #mu#g l"-"1) to cause acute toxicity. The PAH composition pattern in sediments suggest dominance by medium to high molecular weight compounds, and the ...

International Nuclear Information System (INIS)

This paper examines the attractiveness of material mixtures containing special nuclear materials (SNM) associated with reprocessing and the thorium-based LWR fuel cycle. This paper expands upon the results from earlier studies that examined the attractiveness of SNM associated with the reprocessing of spent light water reactor (LWR) fuel by various reprocessing schemes and the recycle of plutonium as a mixed oxide (MOX) fuel in LWR. This study shows that "2"3"3U that is produced in thorium-based fuel cycles is very attractive for weapons use. Consistent with other studies, these results also show that all fuel cycles examined to date need to be rigorously safeguarded and provided moderate to high levels of physical protection. These studies were performed at the request of the United States Department of Energy (DOE), and are based on the calculation of 'attractiveness levels' that has been couched in terms chosen for ...

International Nuclear Information System (INIS)

The concepts of ''fast'' and ''slow'' time scale valence measurements are emphasized by a comparison of L/sub III/ absorption and Mossbauer effect measurements on the temperature induced valence change in EuPd/sub 2/Si/sub 2/. Further the authors show how synchrotron radiation based L/sub III/ measurements of the Ce-valence state can be used to demonstrate electronic structure trends under wide changes in chemical environment. The purpose of this paper is to provide an introduction to researchers in the People's Republic of China to the field of mixed valent rate earth compounds. They hope to illustrate some of the basic concepts in this field, how the field is contributing to the overall insight into the chemical physics of solids and finally how synchrotron radiation measurements in particular are playing a key role in this field.

British Library Electronic Table of Contents (United Kingdom)

In this paper, we investigate the relationship between the subprime asset-backed collateralized debt obligations (CDO) market and Large Complex Financial Institutions (LCFIs). We attempt to account for the dynamics between the ABX index returns and the banks' equity returns through conditioning our analysis on the historical correlation between the variables. Three key results emerge from the analysis. First, we find a positive correlation between movements of the ABX index and the equity returns for all the LCFIs. Second, the volatility of ABX index returns tend to be transmitted to the volatilities of the equity returns of the financial institutions. Third, ABX prices changes lead equity returns changes of the European-based LCFIs. For the US LCFIs a two-way linkage emerges.

Science.gov (United States)

An enantiocontrolled route to aziridinomitosenes had been developed from l-serine methyl ester hydrochloride. The tetracyclic target ring system was assembled by an internal azomethine ylide cycloaddition reaction based on silver ion-assisted intramolecular oxazole alkylation and cyanide-induced ylide generation via a labile oxazoline intermediate (62 to 66). Other key steps include reductive detritylation of 26, methylation of the N-H aziridine 56, oxidation of the sensitive cyclohexenedione 68 to quinone 70, and carbamoylation using Fmoc-NCO. Although the aziridinomitosene tetracycle is sensitive, a range of protecting group manipulations and redox chemistry can be performed if suitable precautions are taken. A study of DNA alkylation by the first C-6,C-7-unsubstituted aziridinomitosene 11a has been carried out, and evidence for DNA cross-link formation involving nucleophilic addition to the quinone subunit is described. PMID:14677970

British Library Electronic Table of Contents (United Kingdom)

This article explores the extent to which and how non-formal education (NFE) contributes to the development of a more diversified basic education system and thus to the achievement of EFA. It outlines the current nature of NFE, the frameworks provided by the EFA movement, and the evolution of reflection, policies and practices in NFE in relation to basic education as a whole. Based on significant developments in various countries across the South, the article also discusses some key challenges that ministries of education and their partners need to face in moving towards relevant and equitable diversity in education. The article posits that, despite the many problems faced by NFE, there is justification for building on its experiences and integrating these within a larger policy and system...

British Library Electronic Table of Contents (United Kingdom)

The US Department of Agriculture (USDA) Nutrient Data Laboratory (NDL) develops and maintains the USDA National Nutrient Databank System (NDBS). Data are released from the NDBS for scientific and public use through the USDA National Nutrient Database for Standard Reference (SR) ( http://www.ars.usda.gov/ba/bhnrc/ndl ). In 1997 the NDL initiated the National Food and Nutrient Analysis Program (NFNAP) to update and expand its food-composition data. The program included: 1) nationwide probability-based sampling of foods; 2) central processing and archiving of food samples; 3) analysis of food components at commercial, government, and university laboratories; 4) incorporation of new analytical data into the NDBS; and 5) dissemination of these data to the scientific community. A key feature and...

British Library Electronic Table of Contents (United Kingdom)

Abstract Objectives- Cyclodextrins are useful solubilizing excipients that have gained currency in the formulator's armamentarium based on their ability to temporarily camouflage undesirable physicochemical properties. In this context cyclodextrins can increase oral bioavailability, stabilize compounds to chemical and enzymatic degradation and can affect permeability through biological membranes under certain circumstances. This latter property is examined herein as a function of the published literature as well as work completed in our laboratories. Key findings- Cyclodextrins can increase the uptake of drugs through biological barriers if the limiting barrier component is the unstirred water layer (UWL) that exists between the membrane and bulk water. This means that cyclodextrins are mo...

International Nuclear Information System (INIS)

A numerical analysis method for melting/solidification phenomena has been developed to evaluate a feasibility of several candidate techniques in the nuclear fuel cycle. Our method is based on the eXtended Finite Element Method (X-FEM) which has been used for moving boundary problems. Key technique of the X-FEM is to incorporate signed distance function into finite element interpolation to represent a discontinuous gradient of the temperature at a moving solid-liquid interface. Construction of the finite element equation, the technique of quadrature and the method to solve the equation are reported here. The numerical solutions of the one-dimensional Stefan problem, solidification in a two-dimensional square corner and melting of pure gallium are compared to the exact solutions or to the experimental data. Through these analyses, validity of the newly developed numerical analysis method has been demonstrated. (author)

Energy Technology Data Exchange (ETDEWEB)

By analogy with the concepts of human learning, we show and introduce a new method to obtain least product cost and price that includes the effect of innovation and technological learning in manufacturing and production. This key result is a new paradigm instead of the usual economic 'power law' formulation. The new analysis is based on extensive analysis of many technological systems, and is directly related to the presence of learning as experience is accumulated. The results agree with the observed data. By using a consistent basis, the method replaces previous empirical 'power law' descriptions of the technological learning curve with a new 'marginal minimum cost equation' (MCE). (author)

Energy Technology Data Exchange (ETDEWEB)

The Procurement and Assistance Data System (PADS) provides a mechanism for collecting, assembling, organizing, and presenting acquisition and assistance data for the Department of Energy (DOE). This handbook and associated documents establish a uniform system to report acquisition/assistance data to PADS for the collection, processing, and dissemination of official statistical data on the Department's acquisition and assistance actions. The data provides, based on information available at the time of request, a basis for any recurring and special reports to the senior procurement executive, Congress, General Accounting Office (GAO), Federal executive agencies, Office of Management and Budget (OMB), and the general public. PADS is also used to satisfy DOE's statutory reporting requirements to the Office of Management Budget, Congress, and other Federal agencies. Accurate and timely collection of PR data is a key element in this ...

British Library Electronic Table of Contents (United Kingdom)

Purpose ? The purpose of this article is to expand the base of supply chain knowledge by applying chaos theory principles to selected supply chain functions. Design/methodology/approach ? Researchers borrow chaos theory from the natural sciences, provide a basic explanation, and then examine how it may be applied to enhance supply chain management techniques. Findings ? Chaos theory principles are used to assist in the examination of forecasting, product design, and inventory management challenges currently facing supply chain practitioners. Research limitations/implications ? Application of chaos theory to various supply chain issues and key functional areas may produce an increase in the level of understanding of supply chain ambiguity and how chaos theory may provide valuable insight in...

Science.gov (United States)

The economic benefits of supplemental fuel injections depend, in part, on the coke replacement ratio. An assessment of the accuracy with which blast furnace coke rate may be measured and a determination of the key drivers of coke rate uncertainty are offered, to provide guidance for experiments in high-rate gas injection. Using statistical analysis tools, an expression for the measurement error associated with the various terms of blast furnace carbon balance is developed. Coke rate calculations based on the material balance are most sensitive to coke carbon content and to proper tracking of hot metal tapping schedule.

CERN Document Server

We have conducted an agent-based simulation of chain bankruptcy. The propagation of credit risk on a network, i.e., chain bankruptcy, is the key to nderstanding largesized bankruptcies. In our model, decrease of revenue by the loss of accounts payable is modeled by an interaction term, and bankruptcy is defined as a capital deficit. Model parameters were estimated using financial data for 1,077 listed Japanese firms. Simulations of chain bankruptcy on the real transaction network consisting of those 1,077 firms were made with the estimated model parameters. Given an initial bankrupt firm, a list of chain bankrupt firms was obtained. This model can be used to detect high-risk links in a transaction network, for the management of chain bankruptcy.

Energy Technology Data Exchange (ETDEWEB)

A mass transfer model has been developed to describe the rate of absorption (or desorption) of H{sub 2}S and CO{sub 2} in aqueous blends of a tertiary and a secondary or a primary amine. The model is based on penetration theory, and all significant chemical reactions are incorporated in the model. The reactions are taken to be reversible, with reactions involving only a proton transfer considered to be at equilibrium. The particular amines studied in this research were methyldiethanolamine (MDEA), a tertiary amine, and diethanolamine (DEA), a secondary amine. Key physicochemical data needed in the model, such as diffusion coefficients, kinetic rate constants, and gas solubilities, were measured. Experimental absorption rates of CO{sub 2} and H{sub 2}S were measured in a model gas-liquid contacting device and were compared with model predictions. Experiments were carried out for single amine solutions (both MDEA and DEA) and for amine blends.

Energy Technology Data Exchange (ETDEWEB)

Generated annually from the Edison Electric Institute's POWER STATISTICS Data Base, the EEI Power Directory provides state-by-state data on all utility-owned steam-electric plants in the US. The 1988 directory contains the following information for approximately 2500 units located at 1000 generating sites around the country: unit age, capacity, fuel type, and operating status. In addition, solid waste disposal methods for fly ash, bottom ash, and sludge are covered for approximately 1500 US coal-fired units. The directory contains a listing of more than 800 environmental managers and key environmental staff at over 300 utilities, with names, addresses, and telephone numbers. Special indices list plants and utility owner-operators.

DEFF Research Database (Denmark)

We examine moving average (MA) filters for estimating the integrated variance (IV) of a financial asset price in a framework where high-frequency price data are contaminated with market microstructure noise. We show that the sum of squared MA residuals must be scaled to enable a suitable estimator of IV. The scaled estimator is shown to be consistent, first-order efficient, and asymptotically Gaussian distributed about the integrated variance under restrictive assumptions. Under more plausible assumptions, such as time-varying volatility, the MA model is misspecified. This motivates an extensive simulation study of the merits of the MA-based estimator under misspecification. Specifically, we consider nonconstant volatility combined with rounding errors and various forms of dependence between the noise and efficient returns. We benchmark the scaled MA-based estimator to subsample and realized kernel estimators and find that ...

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Hydrogen release and distribution in nuclear power plant containment is an important safety issue. Selection of a proper turbulence model is important for accurate estimation of the mixing process. The selection of turbulence model is dictated by the best compromise between accuracy and computational efforts. For this, three different turbulence models, viz. Standard k-{epsilon}, RNG k-{epsilon} and Reynolds Stress Model, based on Reynolds averaged Navier Stokes equations (RANS) approach, were used. The computations were done using the CFD code FLUENT, which is based on the control volume methodology. The computational results were compared with the experimental results of HYMIS test facility, where helium was used to simulate hydrogen. The processes of helium plume rise, multiple plume merging, distribution and mixing were studied. Based on these ...

Energy Technology Data Exchange (ETDEWEB)

Remotely-fielded unattended sensor networks generally must operate at very low power--in the milliwatt or microwatt range--and thus have extremely limited communications bandwidth. Such sensors might be asleep most of the time to conserve power, waking only occasionally to transmit a few bits. RFID tags for tracking or material control have similarly tight bandwidth constraints, and emerging nanotechnology devices will be even more limited. Since transmitted data is subject to spoofing, and since sensors might be located in uncontrolled environments vulnerable to physical tampering, the high-consequence data generated by such systems must be protected by cryptographically sound authentication mechanisms; but such mechanisms are often lacking in current sensor networks. One reason for this undesirable situation is that standard authentication methods become impractical or impossible when bandwidth is severely constrained; if messages are small, a standard digital signature or HMAC will ...

CERN Document Server

We outline to the community the value of a Magellanic Clouds Survey that consists of three components: I) a complete-area, high resolution, multi-band UV-near-IR broadband survey; II) a narrowband survey in 7 key nebular filters to cover a statistically significant sample of representative HII regions and a large-area, contiguous survey of the diffuse, warm ISM; and III) a comprehensive FUV spectroscopic survey of 1300 early-type stars. The science areas enabled by such a dataset are as follows: A) assessment of massive star feedback in both HII regions and the diffuse, warm ISM; B) completion of a comprehensive study of the 30 Doradus giant extragalactic HII region (GEHR); C) development and quantitative parameterization of stellar clustering properties; D) extensive FUV studies of early-type stellar atmospheres and their energy distributions; and E) similarly extensive FUV absorption-line studies of molecular cloud structure and ISM ...

Energy Technology Data Exchange (ETDEWEB)

Conventional methods of financing power generation, transmission and distribution in India cannot keep pace with the ever-growing demand. Alternative methods are discussed. Given the vast growth potential, funding can be by equity or debt capital or a hybrid of these. There is an urgent necessity to develop local capital markets as a source of funds since there are limits to how much can be derived from foreign investors, multilaterals and export credit agencies. The domestic financial institutions have raised large amounts for private investment in other sectors. With the creation of a proper climate and power companies set up with an attractive rate of return, sufficient capital could be forthcoming from both domestic and external markets for the power sector. In other sectors, Indian companies have been able to attract investment through Global Depository Receipts and Euroconvertible Bonds, for example. A key requirement for the power sector ...

Energy Technology Data Exchange (ETDEWEB)

This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and recursive implementation ...

CERN Document Server

CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an ...

Energy Technology Data Exchange (ETDEWEB)

The report contains an overall frame for transformation of knowledge and experience from risk analysis to emergency education. An accident model has been developed to describe the emergency situation. A key concept of this model is uncontrolled flow of energy (UFOE), essential elements are the state, location and movement of the energy (and mass). A UFOE can be considered as the driving force of an accident, e.g., an explosion, a fire, a release of heavy gases. As long as the energy is confined, i.e. the location and movement of the energy are under control, the situation is safe, but loss of confinement will create a hazardous situation that may develop into an accident. A domain model has been developed for representing accident and emergency scenarios occurring in society. The domain model uses three main categories: status, context and objectives. A domain is a group of activities with allied goals and elements and ten specific domains have been investigated: ...

Energy Technology Data Exchange (ETDEWEB)

The 'high-tension distribution line design support system' was developed for the 'work design support system'. This support system is composed of the work outline editor for preparing work details and facility data and the inference engine for preparing practical design plans, and can check system conditions such as voltage drop and deviation from technical standards automatically. The work outline editor takes charge of selection of work items, selective input of system information, and setting of some conditions such as pole position and reserved load onto a system diagram. The inference engine provides the design plan automatically based on the information inputted by the editor. For the design of high-tension distribution line, such various factors as local condition and load sharing of distribution systems should be considered. This design support system attains ...

Energy Technology Data Exchange (ETDEWEB)

The Computational Fluid Dynamics(CFD) study was conducted to assess the new design concept introduced to solve the issues on the flow deviation between SG cassettes and the supporting structure design of the flow distributing plate subjected to the flow induced vibration. Flow field from MCP to the bottom of SG was modeled for 2-dimensional(2D) CFD analysis and then sensitivity analysis on major design parameters was conducted using commercial CFD code, Fluent. The cases for detailed 3D analysis were selected based on the result of 2D analysis and the detailed 3-dimensional(3D) analysis was conducted for these selected cases using Fluent code. Flow field was modeled by RNG model and wall function, 2nd upwind scheme, porous model, structured or hybrid grid. The analysis result shows that the maximum deviation of flow distribution between SG cassettes was reduced upto about 0.1% and the pressure loss from the SG header to SG ...

CERN Document Server

The idea to couple the Treatment Planning System (TPS) to the information on the real boron distribution in the patient is the main added value of the new methodology set-up at DIMNP of University of Pisa, in collaboration with the JRC of Petten (NL). The methodology has been implemented in the new TPS, called BDTPS (Boron Distribution Treatment Planning System), which takes into account the actual boron distribution in the patient brain, while the standard TPS assumes a uniform boron distribution, absolutely far from the reality. Nowadays, Positron Emission Tomography (PET) is able to provide this in vivo information. The new TPS, based on the Monte Carlo technique, has been validated comparing the main BNCT parameters (thermal flux, boron dose, etc.) as measured during the irradiation of a special heterogeneous boron phantom (HEBOM), ad hoc designed, as calculated by the BDTPS and ...

Energy Technology Data Exchange (ETDEWEB)

The compositions of the Earth's crust and mantle, and those of the Moon and Mars, are relatively well known both isotopically and elementally. The same is true of our knowledge of the asteroid belt composition, based on meteorite analyses. Remote measurements of Venus, the Jovian atmosphere, and the outer planet moons, have provided some estimates of their compositions. The Sun constitutes a large majority, > 99%, of all the matter in the solar system. The elemental composition of the photosphere, the visible 'surface' of the Sun, is constrained by absorption lines produced by particles above the surface. Abundances for many elements are reported to the {+-}10 or 20% accuracy level. However, the abundances of other important elements, such as neon, cannot be determined in this way due to a relative lack of atomic states at low excitation energies. Additionally and most importantly, the isotopic composition of the Sun cannot be ...

International Nuclear Information System (INIS)

The paper describes transportation cost of the nuclear off-peak power for a hydrogen production based on water electrolysis in Japan. The power could be obtainable by substituting hydropower and/or fossil fueled power supplying peak and middle demands with nuclear power. The transportation cost of the off-peak power was evaluated to be 1.42 yen/kWh when an electrolyser receives the off-peak power from a 6kV distribution wire. Marked reduction of the cost was caused by the increase of the capacity factor. (author)

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new algorithm for the optimal long-range generation planning for a thermal system with pumped-storage plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. The optimization problem consists of the master problem to determine the annual investment, and the pumped-storage subproblem to determine the optimal pumped-storage operation. The master problem is formulated as a Hamiltonian minimization problem, and the pumped-storage subproblem is solved using the concept of peak-shaving operation on the original load curve.

Energy Technology Data Exchange (ETDEWEB)

Life management system is based on the valid nowadays in Estonian power plants regulation documentation. The system allows to estimate stress distribution in components, find computational assessment of cumulated creep damage, determine when and where it is necessary to cut off the particular number of microsamples or take replicas. Finally, the real metal condition may be assessed on the basis of metallographic specimen research and reasonable 3-R decision - run, repair, replacement - made on further component use. (orig.) 6 refs.

Energy Technology Data Exchange (ETDEWEB)

Directionally solidified nickel-based superalloy DZ4 is an important structural material. However, the grinding burn occurs in grinding processes has hindered the grinding efficiency and dimensional accuracy. This paper investigates the grinding mechanism of this new type of superalloy based on the systematical analyses of variable characteristics of the grinding force, grinding temperature, topography of ground surface, hardness distribution of surface layer, as well as morphology of surface layer from a metallographical point of view. The results will be beneficial to grinding the superalloy with high efficiency and high precision. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The Cu- and Ni-based bulk metallic glass matrix composites were fabricated by spark plasma sintering of a mixture of gas-atomized metallic glass powders and ductile brass powders. The brass powders added for the enhancement of plasticity are well distributed in the matrix after consolidation. The matrix of the composite materials remains as a fully amorphous phase after consolidation process. With increasing the brass content, the level of plasticity strain increased, although the level of strength decreased. The successful consolidation of metallic glass matrix composite with high density was attributed to viscous flow in the supercooled liquid state during spark plasma sintering.

CERN Document Server

Recent studies have revealed a number of striking dependence patterns in high frequency stock price dynamics characterizing probabilistic interrelation between two consequent price increments x (push) and y (response) as described by the bivariate probability distribution P(x,y) [1,2,3,4]. There are two properties, the market mill asymmetries of P(x,y) and predictability due to nonzero z-shaped mean conditional response, that are of special importance. Main goal of the present paper is to put together a model reproducing both the z-shaped mean conditional response and the market mill asymmetry of P(x,y) with respect to the axis y=0. We develop a probabilistic model based on a multi-component ansatz for conditional distribution P(y|x) with push-dependent weights and means describing both properties. A relationship between the market mill asymmetry and predictability is discussed. A possible connection of the model to ...

CERN Document Server

We have conducted a systematic investigation of the origin and underlying physics of the line--line and line--continuum correlations of AGNs, particularly the Baldwin effect. Based on the homogeneous sample of Seyfert 1s and QSOs in the SDSS DR4, we find the origin of all the emission-line regularities is Eddington ratio (L/Ledd). The essential physics is that L/Ledd regulates the distributions of the properties (particularly column density) of the clouds bound in the line-emitting region.

International Nuclear Information System (INIS)

The energy distribution of neutrons generated due to bombardment of 40 MeV alpha particles on thick elemental tantalum is measured using threshold activation detectors. A method of unfolding the neutron spectrum from the activation data based on information-entropy weighted average solution is described. The present unfolding method does not require 'a priori' information about the shape of the solution spectrum. 16 refs. (author).

Energy Technology Data Exchange (ETDEWEB)

Discusses alternative futures for distributing future personal computers, via data communications networks. The author scans and extrapolates some of the advances for impacting the emerging future of information utilities now sprouting up thoroughout the world. In particular he looks at the future of personal computers in the field of artificial intelligence,, for expert knowledge-based systems.

Energy Technology Data Exchange (ETDEWEB)

Numerical errors of PALLAS calculation due to spatial mesh sizes are examined for a typical deep penetration shielding problem of isotropic incident fission neutrons penetrating a 200-cm-thick water slab. The exponential approximation for the source spatial distribution to solve the transport equation based on the direct integration method is verified to be effective for radiation transport in attenuating medium, while the linear approximation employed in the old PALLAS code is found to produce large errors for calculations with large mesh sizes.

Science.gov (United States)

In this work, energy-based features for gear fault diagnosis and prediction are proposed. The instantaneous energy density is shown to obtain high values when defected teeth are engaged. Three methods are compared in terms of sensitivity, reliability and computation effectiveness. The Wigner Ville distribution is contrasted to the wavelet transform and the newly proposed empirical mode decomposition scheme. It is shown that all three methods are capable of a reliable prediction. An empirical law, which relates the energy content to the crack magnitude is established.

International Nuclear Information System (INIS)

The Flux Mapping System (FMS) of 540 MWe PHWR is a system, which is first of its kind used in Indian PHWRs. It is used to compute a detailed flux/power distribution of the reactor core using modal synthesis method .The paper brings out the high availability features of FMS and the software design philosophy. The paper emphasizes on framework based reusable architectural design, which simplifies and speeds up the development of data acquisition systems. (author)

International Nuclear Information System (INIS)

We propose a system for the on-line monitoring of short and medium term radioactive waste repositories. Such a system is distributed, fine-grained, robust, reliable, and must be based on low-cost components. It could, in principle, open new perspectives on the modality of waste packaging and storage. In particular we propose to employ a new family of cheap and powerful micro sensors to be placed in shape of a fine grid around each single drum. (authors)

International Nuclear Information System (INIS)

The aim of the work in this thesis is to investigate the convective and diffusive transport in the TM chemistry transport model, and to investigate some aspects of the consequences for NOx. The large inaccuracy and uncertainty in the description of processes like convection and turbulent diffusion, the strong dependence of the radiative forcing of ozone on its vertical distribution, and the strong dependence of the ozone production on the distribution of NOx, are the main motivation. The availability of the ERA-40 data, where convective data and vertical diffusion coefficients are archived, allows a study of the effect of different convective mass flux sets, and different vertical diffusion coefficients on the model-simulated distribution of tracers. In this thesis the following questions are addressed : (1) How large is the sensitivity of the (model simulated) distribution of ozone and nitrogen oxides ...

Energy Technology Data Exchange (ETDEWEB)

Based on the IAPWS technical guidance on ''Instrumentation for Monitoring and Control of Cycle Chemistry for Steam-Water Circuits of Fossil-Fired and Combined Cycle Power Plants,'' the latest situation regarding instrumentation for nuclear power plants is discussed. As a result of the discussion, it is concluded that: (1) Reliable and safe operation of plants is established by the application of suitable chemical conditions in plant cooling systems, which should be supported by the selection of suitable control targets for monitoring and by the application of reliable instruments. (2) The minimum level of key instrumentation consists of on-line as well as off-line instruments for monitoring the key parameters: - on-line: pH, conductivity, cation conductivity, O{sub 2} and H{sub 2} concentrations, electrochemical corrosion potential; - off-line: radioactive nuclides ({sup 60}Co, {sup ...

DEFF Research Database (Denmark)

Background: Recent studies have developed a murine model of IgE-mediated food allergy based on oral coadministration of antigen and cholera toxin (CT) to establish a maximal response for studying immunopathogenic mechanisms and immunotherapeutic strategies. However, for studying subtle immunomodulating factors or factors effective during response initiation, this maximal response-based model is less suitable due to a lack of sensitivity. Therefore, in attempts to identify essential parameters to fine-tune the immune response towards a submaximal level, potentially more sensitive, we were interested in characterizing the individual effects of the parameters in the CT-based model: CT dose, antigen type and dose, and number of immunizations. Methods: BALB/c mice were orally sensitized weekly for 3 or 7 weeks with graded doses of CT and various food antigens (soy-trypsin inhibitor, ovalbumin or ovomucoid). Antigen-specific ...

International Nuclear Information System (INIS)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360 nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8 mA, and a slow photoresponse with a rise time of 5 min and a decay time of 7 min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the decrease of the barrier height between crystallites. The relaxation time constant #tau# obtained from the curve fitting represents the time accumulation during the process. The ...

CERN Document Server

The LHC magnet tests operation team developed various innovative techniques, particularly since early 2004, to complete the superconductor magnet tests by Feb. 2007. Overall and cryogenic priority handling, rapid on-bench thermal cycling, rule-based goodness evaluation on round-the-clock basis, multiple, mashed web systems are some of these techniques applied with rigour for successful tests completion in time. This paper highlights these operation empowerment tools which had a pivotal role for success. A priority handling method was put in place to enable maximum throughput from twelve test benches, having many different constraints. For the cryogenics infrastructure, it implied judicious allocation of limited resources to the benches. Rapid On-Bench Thermal Cycle was a key strategy to accelerate magnets tests throughput, saving time and simplifying logistics. First level magnet appraisal was developed for 24 hr decision making so as to ...

International Nuclear Information System (INIS)

In order to effectively recover uranium, rotation speed of solid cathode was examined, and effect of uranium concentration and current density on electrodeposition were confirmed. And the potentiostatic and galvanostatic electrorefining experiments were conducted. Element used in the experiments were Zr, Nd, La chlorides. The reduction potentials of chlorides metals on liquid Cd cathode were measured by cyclic voltammetry experiments. The electrowinning experiments were performed in order to recover small amounts of uranium in salt. Experimental set-up for the batch type reductive extraction experiments were developed and installed. On the base of experimental results of batch type, multi-stage extraction equipment was set-up, and optimum number of stage and recover yield were measured. In the oxidative extraction study is examine selective separation behavior of the rare earth metals from alloy composed of actinide and lanthanide metals to determine the effective ...

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) Headquarters and associated contractors have developed an IBM PC-based software package that estimates costs, schedules, and public and occupational health risks for a range of mixed-waste management options. A key application of the software package is the comparison of various waste-treatment options documented in the draft Site Treatment Plans prepared in accordance with the requirements of the Federal Facility Compliance Act of 1992. This automated Systems Analysis Methodology consists of a user interface for configuring complexwide or site-specific waste-management options; calculational algorithms for cost, schedule and risk; and user-selected graphical or tabular output of results. The mixed-waste management activities modeled in the automated Systems Analysis Methodology include waste storage, characterization, handling, transportation, treatment, and disposal. Analyses of treatment options identified ...

DEFF Research Database (Denmark)

Introducing intelligence by means of cognition for managing, protecting, processing, and delivering of information in mobile communication systems is the way towards ubiquitous, converged and secure communications. In this context, this paper introduces the concept of quality of information (QoI). QoI means QoS while all the requirements for dependability, security, privacy and trust are satisfied at the highest possible level. This work proposes and describes an approach to network monitoring in a heterogeneous communication environment based on use of cognitive techniques and learning predictive algorithms (e.g., fuzzy logic). These methodologies are used to create an autonomy in the decision making process that is based on the calculation of key performance indicators (KPIs), which in their turn would trigger the needed radio resource management algorithms. The expected output is an improved network performance in terms ...

Energy Technology Data Exchange (ETDEWEB)

Metals for potential use in the dissociator and the synthesizer reactors of a distributed solar receiver thermochemical transport loop utilizing SO/sub 3//SO/sub 2//O/sub 2/ molecular chemistry includes stainless steels and iron-base, nickel-base and cobalt-base superalloys. We tested these alloys in SO/sub 2//O/sub 2/ mixtures and SO/sub 3/ gas at 500/sup 0/C and 900/sup 0/C, respectively, for times of up to four weeks. Weight gain measurements were used to determine the oxidation/sulfidation kinetics and electron microprobe analysis was used to measure penetration of oxygen and sulfur into the metal and to identify the formation of internal oxides and sulfides. Results of these tests showed that the most promising candidates are those containing sufficient quantities of both aluminum and chromium alloying additions to be alumina and chromia formers, such as Kanthal A-1, Nimonic 105 and Cabot 214.

British Library Electronic Table of Contents (United Kingdom)

The characteristics of aerosol generation were studied experimentally in an ammonia-based wet flue gas desulfurization process. Particle size distributions and concentrations, morphologies and compositions before and after desulfurization were measured using an electrical low pressure impactor and scanning electron microscopy, respectively. The results show that aerosols can be generated between ammonia and sulfur dioxide resulting in gas-phase reaction and the aerosol concentration at the outlet of scrubber is significantly higher than at the inlet. Before desulfurization the particles are primarily silica-alumina minerals including O, Al, Si and C, while after ammonia-based desulfurization aerosol particles have smooth surfaces with regular structures, such as cubic and prismatic crystal...

Energy Technology Data Exchange (ETDEWEB)

Based on the Morlet wavelet transformation and Wigner-Ville distribution (WVD), we present a wind turbine fault diagnosis method in this paper. Wind turbine can be damaged by moisture absorption, fatigue, wind gusts or lightening strikes. Due to this reason, there is an increasing need to monitor the health of these structures. Vibration analysis is the best-known technology applied in wind turbine condition monitoring, in which the time-frequency analysis techniques such as Wigner-Ville distribution (WVD) are widely used. Theoretically WVD has an infinite resolution in time-frequency domain. For early wind turbine fault signals, however, there are two main difficulties in WVD analysis. One is strong noise signals in the background and the other is cross terms in WVD itself. In this paper, continuous wavelet transformation (CWT) is employed to filter useless noise in raw vibration signals, and auto terms window (ATW) ...

British Library Electronic Table of Contents (United Kingdom)

Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between...

International Nuclear Information System (INIS)

Consideration is given to the process of the formation of a titanium sponge alloyed with niobium or tantalum, in the joint metallic reduction of titanium, niobium and tantanum chlorides. A percentage composition of the phases observed and the structure of the alloyed sponge have been studied. It is shown that after one remelting operation of the alloyed sponge the alloys of titanium with niobium and tantalum have a uniform component distribution. At the stage of chloride reduction there appear solid solutions based on titanium and an alloying component. The stage of vacuum separation of the reaction mass is associated with a mutual dissolution of the primary phases and the formation of the solid solutions of the alloyed titanium sponge, which, by their composition, are close to the desired alloy composition. The principal features of the formation of a titanium sponge alloyed with niobium and tantalum are in a perfect agreemet with those ...

Energy Technology Data Exchange (ETDEWEB)

A flow pattern or flow regime is the characteristics spatial distribution of the phases of fluid in a duct. Since heat transfer and pressure drop are dependent on the characteristic distribution of the phases, it is necessary to describe flow patterns in an appropriate manner so that a hydrodynamic or heat transfer theory applicable to that pattern can be chosen. The objective of the present analysis is to create a flow regime map based on physical modeling of vapor/liquid interaction phenomena in a microgravity environment. In the present work, four basic flow patterns are defined: dispersed flow, stratified flow, slug flow, and annular flow. Fluid properties, liquid and vapor flow rates, and pipe size were chosen as the principal parameters. It is assumed that a transition from one flow pattern to another will occur when there is a change in the dominant force which controls that flow pattern. The forces considered in ...

International Nuclear Information System (INIS)

This Letter reports the first experimental results from the world's first distributed optical-klystron (DOK) free-electron laser (FEL), the DOK-1 FEL, at Duke University. The DOK-1 FEL is a hybrid system, comprised of four wigglers: two horizontal and two helical. With the DOK-1 FEL, we have obtained the highest FEL gain among all storage ring based FELs at 47.8% (#+-#2.7%) per pass. We have also demonstrated that the FEL gain can be enhanced by increasing electron bunching using wigglers with a different polarization. Furthermore, we have realized controlled polarization switches of the FEL beam by a nonoptical means through the manipulation of a buncher magnet.

CERN Document Server

One of the salient features of human perception is its invariance under dilatation in addition to the Euclidean group, but its non-invariance under special conformal transformation. We investigate a holographic approach to the information processing in image discrimination with this feature. We claim that a strongly coupled analogue of the statistical model proposed by Bialek and Zee can be holographically realized in scale invariant but non-conformal Euclidean geometries. We identify the Bayesian probability distribution of our generalized Bialek-Zee model with the GKPW partition function of the dual gravitational system. We provide a concrete example of the geometric configuration based on a vector condensation model coupled with the Euclidean Einstein-Hilbert action. From the proposed geometry, we study sample correlation functions to compute the Bayesian probability distribution.

International Nuclear Information System (INIS)

The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the ...

International Nuclear Information System (INIS)

Utilities are evaluating several electric generation and storage (G ampersand S) technologies for distributed utility (DU) applications. Attributes of leading DU technologies and implications for photovoltaics (PV) are described. Included is a survey of present and projected cost and performance for: (1) small, advanced combustion turbines (CTs); (2) advanced, natural gas-fired, diesel engines (diesel engines); and (3) advanced lead-acid battery systems (batteries). Technology drivers and relative qualitative benefits are described. A levelized energy cost-based cost target for PV for DU applications is provided. The analysis addresses only relative cost, for PV and for three selected alternative DU technologies. Comparable size, utility, and benefits are assumed, although relative value is application-specific and often technology- and site-specific.

International Nuclear Information System (INIS)

Using a realistic three-body model, angular distributions for the "1"6O(d,p)"1"7O(1/2"+) reaction, based on the channel coupling array (CCA) theory and various forms of the coupled reaction channel (CRC) method are compared. Despite the different forms and theoretical foundations of these methods, they yield similar angular distributions, within the bound state approximations used herein. The expected breaking of time reversal inveriance in the approximated CCA theory is quite small over most of the angular range. Of all the methods used, coupling effects in the forward directions are largest for the post form of the CRC, indicating that it is the least reliable of the CRC forms for fitting data. (Auth.).

British Library Electronic Table of Contents (United Kingdom)

An analytical method was proposed for calculating radiative fluxes incident on a planar circular detector from a volume multiple point chemi- or bio-luminescent source inside a coaxial cylindrical reactor. The method was designed for a cylindrical reactor when the surface reflections were neglected and when chemi- or bio-luminescence reaches a detector embedded in the same homogeneous optical medium as the point emitters of the volume multiple point source model. The radiative fluxes from arbitrarily distributed point emitters were expressed by one generalized quadruple-integral formula. Then some double- and single-integral formulas were obtained for calculating radiative fluxes from identically radiating point emitters uniformly distributed within the reactor. Selected results were compu...

International Nuclear Information System (INIS)

Thermal fatigue is one of the key factors governing the lifetime of the divertor plate. Tungsten is a promising candidate to cover the surface of the divertor plate in the design of the international thermonuclear experimental reactor (ITER). The W/Cr-bronze divertor small scale mock-ups were manufactured by hot isostatic pressing (HIPing) technique. Thermal fatigue tests of W/Cr-bronze divertor mock-ups have been carried out by an electron beam facility. The mock-ups were tested under a cyclic surface heat flux of 9 MW m"-"2 for 1000 cycles. The electron beam was loaded on the mock-up surface for 20 s and unloaded for 20 s, alternately. The flow rate of water coolant was 0.1 L s"-"1. The 0.3 mm diameter NiCr-NiSi thermocouples were used to monitor the temperature distribution of the mock-up. It was found that the maximum temperature of the tungsten surface was about 400 degree sign C. The saturated temperature at the joint of tungsten and ...

Science.gov (United States)

Georgia Fish: Freshwater fish distributions,classification, conservation status, and distribution comments for Georgia....

British Library Electronic Table of Contents (United Kingdom)

For companies, relationships with external actors may constitute intangible assets. Many firms have put in place key account management programs in order to pay sufficient attention to strategically important customers and the marketing literature has studied such programs. However, a company's relationship portfolio also comprises relationships with other types of actors. The objective of this paper is to show that ? across the different types of external relationships a company may develop ? some relationships have more importance than others and, hence, are key. The authors argue that, as a consequence, the keyness of certain relationships has led to the emergence of approaches which can be referred to as key relationship management. For this purpose, the authors first present empirical...

International Nuclear Information System (INIS)

High-resolution sequence stratigraphy taking base-level cycles as interface of reference was developed rapidly in recent years. Its greatest predominance lies in that it can be applied to multi-controled continental sedimentary basins and can effectively improve accuracy and distinguishability of sequence stratigraphy analysis. Principles of base-level cycles can also be applied to the research and practice of the exploration and exploitation of sandstone-type uranium deposits as they control the spatial distribution, porosity, the permeability and the sealing ability of sandstone and mudstone, and stacking patterns of strata configuration. Taking Dongsheng uranium deposits as an example, the application of base-level cycles to exploration and exploitation of sandstone uranium deposits was analyzed. It is suggested that favorable strata framework of sandstone and mudstone was developed very well in the ...

CERN Document Server

The data obtained by the recent modern sky surveys enable detailed studies of the stellar distribution in the multi-dimensional space spanned by spatial coordinates, velocity and metallicity, from the solar neighborhood all the way out to the outer Milky Way halo. While these results represent exciting observational breakthroughs, their interpretation is not simple. For example, traditional decomposition of the thin and thick disks predicts a strong correlation in metallicity and kinematics at $\\sim$1 kpc from the Galactic plane; however, recent SDSS--based work has demonstrated an absence of this correlation for disk stars. Instead, the variation of the metallicity and rotational velocity distributions can be modeled using non--Gaussian functions that retain their shapes and only shift as the distance from the mid--plane increases. To fully contextualize these recent observational results, a detailed comparison with ...

Energy Technology Data Exchange (ETDEWEB)

Monodisperse noble metal nanoparticles are of tremendous interest for numerous applications, such as surface-enhanced Raman spectroscopy, catalysis or biosensing. However, preparation of monodisperse metal nanoparticles is still a challenging task, because typical preparation methods yield nanoparticle ensembles with broad shape and/or size distributions. To overcome this drawback, tailoring of metal nanoparticles with laser light has been developed, which is based on the pronounced shape- and size-dependent optical properties of metal nanoparticles. I will demonstrate that nanoparticle tailoring with ns-pulsed laser light is a suitable method to prepare nanoparticle ensembles with a narrow shape and/or size distribution. While irradiation with ns-pulsed laser light during nanoparticle growth permits a precise shape tailoring, post-grown irradiation allows a size tailoring. For example, the initial broad Gaussian size ...

Energy Technology Data Exchange (ETDEWEB)

A field survey on cadmium, lead, copper, and zinc was performed in Semarang, the fifth largest city in Indonesia. Water, sediment, and fish samples were collected from 101 grids of 2 x 2 km. The objectives of the study were (1) to identify the spatial distribution of metals in the sediments of the greater Semarang area, (2) to estimate the background concentrations of the metals present in Semarang, (3) to provide a simple tool for deriving standards for metals in the sediment, and (4) to explore the potential use of the guppy (Lebistes reticulatus) as a bioindicator of urban metal pollution. To map the spatial distribution of the metals, concentrations of each metal in sediment were plotted against the corresponding city coordinate. On the basis of these plots, background concentrations of the metals were estimated. A combined pollution index can be derived thereafter by calculating the difference between metals concentrations from a ...

Energy Technology Data Exchange (ETDEWEB)

The consistency of different instruments and methods for measuring two-dimensional (2D) power spectral density (PSD) distributions are investigated. The instruments are an interferometric microscope, an atomic force microscope (AFM) and the X-ray Reflectivity and Scattering experimental facility, all available at Lawrence Berkeley National Laboratory. The measurements were performed with a gold-coated mirror with a highly polished stainless steel substrate. It was shown that these three techniques provide essentially consistent results. For the stainless steel mirror, an envelope over all measured PSD distributions can be described with an inverse power-law PSD function. It is also shown that the measurements can be corrected for the specific spatial frequency dependent systematic errors of the instruments. The AFM and the X-ray scattering measurements were used to determine the modulation transfer function of the interferometric microscope. ...

Energy Technology Data Exchange (ETDEWEB)

This paper compares two systems providing advanced functions for real-time management of power distribution networks developed in Finland and in France. The overall aim of these systems is to minimize the operational costs (e.g. power losses, outage level, thermal limits). These are to be integrated with a Supervision Control and Data Acquisition system (SCADA) and heterogeneous databases such as network and geographical information systems (AM/FM/GIS). The Finnish system called OPERA has been developed in the past years at the Tampere University of Technology. It is now commercialised by the Versoft Ltd software company and used in 11 control centers. The French system, called AUSTRAL is in the industrialization phase by now at the Research and Development Division of EDF. It will be put into real operation in three distribution utilities in 1997. In this paper, we briefly introduce both systems and discuss their similarities and differences ...

International Nuclear Information System (INIS)

Nuclear knowledge is the basis for almost all nuclear activities, and education and training are the most fundamental means to transfer knowledge from one generation to the next. Understanding means and trends in knowledge transfer through education and training thus deserves a closer examination. In the past years, a number of trends and questions in nuclear knowledge, education and training have emerged. With declining student enrolment numbers and a general stagnation of the use of nuclear power in some of the IAEA's Member States, the issue of a slow erosion of the knowledge base and the possibility of loosing knowledge has become increasingly important, in particular if seen against the background of a possible renaissance of nuclear power in the future. In other Member States, an expansion of nuclear power is expected, with a corresponding need for human resources. As a result, in many Member States education and training of the next generation and succession ...

Energy Technology Data Exchange (ETDEWEB)

The NGDRS has facilitated 85% of cores, cuttings, and other data identified available for transfer to the public sector. Over 12 million linear feet of cores and cuttings, in addition to large numbers of paleontological samples and are now available for public use. To date, with industry contributions for program operations and data transfers, the NGDRS project has realized a 6.5 to 1 return on investment to Department of Energy funds. Large-scale transfers of seismic data have been evaluated, but based on the recommendation of the NGDRS steering committee, cores have been given priority because of the vast scale of the seismic data problem relative to the available funding. The rapidly changing industry conditions have required that the primary core and cuttings preservation strategy evolve as well. Additionally, the NGDRS clearinghouse is evaluating the viability of transferring seismic data covering the western shelf of the Florida Gulf Coast. AGI remains ...

Energy Technology Data Exchange (ETDEWEB)

Chemical admixtures are used in dam construction to improve plasticity of the dry materials mixture over time. Roller compacted concrete (RCC) has been used on many dam projects in China. However, the use of RCC has frequently resulted in water reduction problems. This paper provided details of an admixture based on polycarboxylate ether (PCE) which was developed to improve the quality of RCC constructions at the JinHong dam in China. Use of the polymer at the JinHong dam resulted in a vibration sensitive concrete that was sustained over time. Under identical mix-design and compaction conditions in the laboratory, specific gravity of the RCC was increased from 2417 kg/m{sup 3} to 2463 kg/m{sup 3}. The high specific gravity of the material resulted in satisfactory strength data from the dam project. The key-ratio of the splitting tensile strength versus compressive strength was higher than 8 per cent in all cases. A key ...

Science.gov (United States)

Pentaerythritol tetranitrate (PETN) is a relatively sensitive explosive used in many electroexplosive devices as well as in medicine. Of primary interest to LLNL is its use in items such as exploding bridgewire (EBW) detonators and exploding bridge foil initiators (EFI). In these devices the crystalline powder is pressed into a granular, low-density compact that can be initiated by an exploding wire or foil. The long-term stability of this pressed compact is of interest to weapon stockpile lifetime prediction studies. Key points about potential aging mechanisms can be summarized as follows: (1) There are a number of factors that can contribute to PETN instability. These include particle size, polymorphic phase transitions, crystal structure, impurities, moisture, occlusions, chemical incompatibility and biological (microorganism) action. of these factors the most important for long-term aging of high surface area powders used in detonators appears to be that of ...

UK PubMed Central (United Kingdom)

AMP-activated-protein-kinase (AMPK) is a key sensor and regulator of cellular and whole-body energy metabolism and plays a key role in regulation of lipid metabolism. Since lipid metabolism...Full Text Available

International Nuclear Information System (INIS)

We introduce a novel search technique that can identify trans-Neptunian objects in three to five exposures of a pointing within a single Hubble Space Telescope (HST) orbit. The process is fast enough to allow the discovery of candidates soon after the data are available. This allows sufficient time to schedule follow-up observations with HST within a month. We report the discovery of 14 slow-moving objects found within 50 of the ecliptic in archival data taken with the Wide Field Channel of the Advanced Camera for Surveys. The luminosity function of these objects is consistent with previous ground-based and space-based results. We show evidence that the size distribution of both high and low inclination populations is similar for objects smaller than 100 km, as expected from collisional evolution models, while their size distribution differs for brighter objects. We suggest that the two populations ...

CERN Document Server

The traditional way of estimating the gravitational field from observed motions of test objects is based on the virial relation between their kinetic and potential energy. We find a more efficient method. It is based on the natural presumption that the objects are observed at a random moment of time and therefore have random orbital time phases. The proposed estimator, which we call "orbital roulette", checks the randomness of the phases. The method has the following advantages: (1) It estimates accurately Keplerian (point-mass) potentials as well as non-Keplerian potentials where the unknown gravitating mass is distributed in space. (2) It is a complete statistical estimator: it checks a trial potential and accepts it or rules it out with a certain significance level; the best-fit measurement is thus supplemented with error bars at any confidence level. (3) It needs no a priori assumptions about the ...

CERN Document Server

The design of a small injection linac for a compact medical synchrotron is discussed. The linac design is based on interdigital H-type (IH) drift-tube structure with alternative phase focusing (APhF). A high acceleration rate and an absence of magnetic lenses inside drift-tubes reduce the cost and length of APhF-IH linac in comparison with HIMAC linac based on Alvarez structure with magnet quadrupoles inside drift-tubes. To reduce effects of emittance growth, the RFQ structure is used in front of the APhF linac. In such linac layout, the current transmission of a carbon beam can reach up to 90-100%. In this report, the basic parameters of whole linac are presented, while the design of APhF structure is considered in details. Two reference designs of 4 MeV/u 200 MHz APhF linacs with different voltage distributions along the whole tank have been generated and analyzed numerically. For the first design, a constant voltage ...

CERN Document Server

We present a new method based on the N-point probability distribution (pdf) to study non-Gaussianity in cosmic microwave background (CMB) maps. Likelihood and Bayesian estimation are applied to a local non-linear perturbed model up to third order, characterized by a linear term which is described by a Gaussian N-pdf, and a second and third order terms which are proportional to the square and the cube of the linear one. We also explore a set of model selection techniques (the Akaike and the Bayesian Information Criteria, the minimum description length, the Bayesian Evidence and the Generalized Likelihood Ratio Test) and their application to decide whether a given data set is better described by the proposed local non-Gaussian model, rather than by the standard Gaussian temperature distribution. As an application, we consider the analysis of the WMAP 5-year data at a resolution of around 2 degrees. At this angular scale (the ...

International Nuclear Information System (INIS)

A study trip to a biomass gasification plant in Germany took place from 13-15 November 2000. The goal of the trip was to obtain information on German developments, experience, and possibilities in the field of biomass gasification. The participants were representatives of Dutch parties in the energy sector: waste sector, manufacturers, producers, policy makers and consultants. The most important feature was the visit to plants that were in operation. Due in particular to the new EEG (Emeuerbare-Energien-Gesetz/Renewable Energy) legislation, German policy makers have created an initial market for sustainable energy with a degree of success. The key feature is that EEG makes projects 'bankable' by guaranteeing a return delivery compensation. An EEG-type scheme designed to accelerate the development of sustainable energy could be an interesting instrument also for the Netherlands. The plan was to visit four plants and have a number of presentations in a period of ...

Energy Technology Data Exchange (ETDEWEB)

Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, ...

Energy Technology Data Exchange (ETDEWEB)

A review of current daylighting design tools indicates that over 30 tools are now available, including nomographs, protractors, overlays, and programs for micro-, mini-, and mainframe computers. Computer-based tools allow testing and analyzing of more design alternatives under a wider variety of conditions than was previously practical with slower techniques, but they have not fundamentally changed the information available to the design professional. These tools are applicable to certain limited functions of the design process and do not address the varying information needs of the designer at various points in the design process. We describe a concept for a computer-based building envelope design tool that is structured to overcome many of the limitations of the existing tools. The tool would address daylighting design in the context of the overall building envelope design, covering a range of environmental quality issues in addition to ...

Science.gov (United States)

... Uninterrupted access to and use of critical infrastructure in the Arabian Gulf region are key to the successful prosecution of the Global War on Terror ...

Science.gov (United States)

The previously unknown property of the optical speckle pattern reported. The interference of a speckle with the counterpropagating phase-conjugated (PC) speckle wave produces a randomly distributed ensemble of a twisted entities (ropes) surrounding optical vortex lines. These entities appear in a wide range of a randomly chosen speckle parameters inside the phase-conjugating mirrors regardless to an internal physical mechanism of the wave-front reversal. These numerically generated interference patterns are relevant to the Brillouin PC mirrors and to a four-wave mixing PC mirrors based upon laser trapped ultracold atomic cloud.

CERN Document Server

We show the propagation of regularity, uniformly in time, for the scaled solutions of the inelastic Maxwell model for small inelasticity. This result together with the weak convergence towards the homogenous cooling state present in the literature implies the strong convergence in Sobolev norms and in the $L^1$ norm towards it depending on the regularity of the initial data. The strategy of the proof is based on a precise control of the growth of the Fisher information for the inelastic Boltzmann equation. Moreover, as an application we obtain a bound in the $L^1$ distance between the homogeneous cooling state and the corresponding Maxwellian distribution vanishing as the inelasticity goes to zero.

Energy Technology Data Exchange (ETDEWEB)

This paper describes the design of a high-voltage negative ion source based on a magnetically insulated diode and generating microsecond pulses. Plane an cylindrical cathodes have been tested. The spatial and angular distributions of negative ions in the beam have been measured. The content of negative ions with different masses in the beam are given. The ion current density measured by a Faraday cup was up to 1 A/cm{sup 2} for the radial beam and 30-40 A/cm{sup 2}.

International Nuclear Information System (INIS)

This article describes version 3.006 of Nuance, an advanced and freely available neutrino generator written by Dave Casper of University of California, Irvine. Source codes of the program are publicly available. This description is based on Dave Casper's article '' The Nuance Neutrino Physics Simulation and the Future '', http://nuint.ps.uci.edu/nuance/files/ nuancenuint01.pdf , Nuance website at http://nuint.ps.uci.edu/ nuance/ , README.txt file provided in the src folder of Nuance distribution, and my own experience as a Nuance user. (author)

International Nuclear Information System (INIS)

An attempt was made to quantify the radiation risk of diagnostic radiology. After a general introduction of terms as radiation damage, radiation risk and effective dose equivalent, based on publications of the ICRP, somatic dose indexes were computed for several radiologic investigations, that comprise organ doses committed to red bone marrow, lung, female breast and thyroid with and without considering the rest of the body. The dose for the rest of the body was assumed to be equal to the dose received by the red bone marrow, that is also distributed over the whole body. Neglecting the exposure of the rest of the body resulted in an insignificant increase in the estimated somatic risk, with its experimental determination not being necessary. (author).

Energy Technology Data Exchange (ETDEWEB)

To expand the information base on molecular accessibility in solvent swelled coal, Argonne Premium Coal Samples (APCS) were swelled in polar, basic solvents before and after moisture loss and upon air oxidation. So far studies have been reported on the changes in pore size distribution as a function of temperature when polar basic swelling solvents are used. Additional studies employing EPR spin probe techniques performed on the breaking up of the hydrogen bonding between bedding planes were later confirmed by magnetic resonance imaging at Argonne National Lab and the University of Illinois.

Science.gov (United States)

The accuracy of stabilized, turreted gun systems like the 120mm gun on the M1A2 Abrams tank and the 30mm gun on the Apache helicopter are limited by, among other things, structural flexure of the gun barrel and support structure. An advanced actuation system based on piezoelectric translators and an optical fiber strain sensing system are described in conjunction with a rapid prototyping workstation for the design of distributed parameter control systems to actively minimize the effects of vibrations caused by traversing rough terrain or weapon firing.

Energy Technology Data Exchange (ETDEWEB)

We discuss the inclusive production of D{sup *{+-}} mesons in {gamma}p collisions at DESY HERA, based on a calculation at next-to-leading order in the general-mass variable-flavor-number scheme. In this approach, MS subtraction is applied in such a way that large logarithmic corrections are resummed in universal parton distribution and fragmentation functions and finite mass terms are taken into account. We present detailed numerical results for a comparison with data obtained at HERA and discuss various sources of theoretical uncertainties. (orig.)