International Nuclear Information System (INIS)

Convolution/superposition (C/S) is regarded as the standard dose calculation method in most modern radiotherapy treatment planning systems. Different implementations of C/S could result in significantly different dose distributions. This paper addresses two major implementation issues associated with collapsed cone C/S: one is how to utilize the tabulated kernels instead of analytical parametrizations and the other is how to deal with voxel size effects. Three methods that utilize the tabulated kernels are presented in this paper. These methods differ in the effective kernels used: the differential kernel (DK), the cumulative kernel (CK) or the cumulative-cumulative kernel (CCK). They result in slightly different computation times but significantly different voxel size effects. Both simulated and ...

International Nuclear Information System (INIS)

The convolution/superposition calculations for radiotherapy dose distributions are traditionally performed by convolving polyenergetic energy deposition kernels with TERMA (total energy released per unit mass) precomputed in each voxel of the irradiated phantom. We propose an alternative method in which the TERMA calculation is replaced by random sampling of photon energy, direction and interaction point. Then, a direction is randomly sampled from the angular distribution of the monoenergetic kernel corresponding to the photon energy. The kernel ray is propagated across the phantom, and energy is deposited in each voxel traversed. An important advantage of the explicit sampling of energy is that spectral changes with depth are automatically accounted for. No spectral or ...

British Library Electronic Table of Contents (United Kingdom)

A convolution/superposition method is proposed for use with primary and scatter dose kernels formed for energy bins of X-ray spectra reconstructed as a function of off-axis distance. It should be noted that the number of energy bins is usually about ten, and that the reconstructed X-ray spectra can reasonably be applied to media with a wide range of effective Z numbers, ranging from water to lead. The study was carried out for 10-MV X-ray doses in water and thorax-like phantoms with the use of open-jaw-collimated fields. The dose calculations were made separately for primary, scatter, and electron contamination dose components, for which we used two extended radiation sources: one was on the X-ray target and the other on the flattening filter. To calculate the in-air beam intensities at po...

International Nuclear Information System (INIS)

A number of procedures in diagnostic radiology and cardiology make use of long exposures to x-rays from fluoroscopy units. Although numerous studies have been performed to measure or calculate skin dose from these procedures, there have only been a handful of studies to determine the dose to the other organs. This thesis was focused on devising a method to calculate the absorbed dose to underlying tissues and organs. The work was performed in several stages. First, a commercial convolution/superposition-based treatment planning system used in radiation oncology was modified and complemented to make it usable with the low energies of x-rays used in diagnostic radiology. This required generation of energy deposition kernels in the kilovoltage energy range. The kernels were generated using the EGS4 Monte Carlo system of codes and added to the treatment planning ...

International Nuclear Information System (INIS)

Accurate dose calculation in radiation treatment planning is most important for successful treatment. Since human body is composed of various materials and not an ideal shape, it is not easy to calculate the accurate effective dose in the patients. Many methods have been proposed to solve inhomogeneity and surface contour problems. Monte Carlo simulations are regarded as the most accurate method, but it is not appropriate for routine planning because it takes so much time. Pencil beam kernel based convolution/superposition methods were also proposed to correct those effects. Nowadays, many commercial treatment planning systems have adopted this algorithm as a dose calculation engine. The purpose of this study is to verify the accuracy of the dose calculated from pencil beam kernel based treatment planning system comparing to Monte Carlo simulations and measurements especially in ...

Energy Technology Data Exchange (ETDEWEB)

The mechanisms involved in amino acid and sugar uptake by developing maize kernels were investigated. In the pedicel region of maize kernel, the site of nutrient unloading from phloem terminals, amino acids are accumulated in considerable amounts and undergo significant interconversion. A wide spectrum of enzymatic activities involved in the metabolism of amino acids is observed in these tissues. Subsequently, amino acids are taken up by the endosperm tissue in processes which require energy and the presence of carrier proteins. Conversely, no evidence was found that energy and carriers are involved in sugar uptake. This process of sugar uptake is not inhibited by metabolic inhibitors and shows nonsaturable kinetics, but the uptake is pH-dependent. L-glucose is taken up at a significantly reduced rate in comparison to D-glucose uptake. Based on analysis of radioactivity distribution among sugar ...

International Nuclear Information System (INIS)

Techniques for reducing computation time in 3D photon dose calculations are addressed with specific emphasis given to the convolution/superposition approach. A single polyenergetic superposition model calculating absorbed dose per incident photon fluence (Gy cm"2) was developed in terms of TERMA and a total energy deposition kernel (a total point spread function). A novel approach was devised for reducing calculation time. The method, named the CF method, was based on the use of a conventional, fast model (here a modified power-law method was used) for the generation of 3D dose distributions on a fine dose matrix. Superposition calculations were carried out on a coarse matrix and calculation speed was increased simply by reducing the number of calculations. A set of correction factors was derived on the coarse grid from the ratio of the dose values from superposition to those from ...

Energy Technology Data Exchange (ETDEWEB)

Validation of nuclear power reactor signals is often performed by comparing signal prototypes with the actual reactor signals. The signal prototypes are often computed based on empirical data. The implementation of an estimation algorithm which can make predictions on limited data is an important issue. A new machine learning algorithm called support vector machines (SVMS) recently developed by Vladimir Vapnik and his coworkers enables a high level of generalization with finite high-dimensional data. The improved generalization in comparison with standard methods like neural networks is due mainly to the following characteristics of the method. The input data space is transformed into a high-dimensional feature space using a kernel function, and the learning problem is formulated as a convex quadratic programming problem with a unique solution. In this paper the authors have applied the SVM method for ...

CERN Document Server

Standard methods in non-linear analysis are used to show that there exists a parabolic branching of solutions of the Lichnerowicz-York equation with an unscaled source. We also apply these methods to the extended conformal thin sandwich formulation and show that if the linearised system develops a kernel solution for sufficiently large initial data then we obtain parabolic solution curves for the conformal factor, lapse and shift identical to those found numerically by Pfeiffer and York. The implications of these results for constrained evolutions are discussed.

International Nuclear Information System (INIS)

A method has been developed for calibration of CT-numbers to volumetric electron density distributions using tissue substitutes of known elemental composition and experimentally determined electron density. This information have been used in a dose calculation method based on photon and electron interaction processes. The method utilizes a convolution integral between the photon fluence matrix and dose distribution kernels. Inhomogeneous media are accounted for using the theorems of Fano and O'Connor for scaling dose distribution kernels in proportion to electron density. For clinical application of a calculated dose plan, a method for prediction of accelerator output have been developed. The methods gives the number of monitor units that has to be given to obtain a certain absorbed dose to a point inside an irregular, inhomogeneous object. ...

UK PubMed Central (United Kingdom)

Sectors of Zea mays cobs, with and without kernels were cultured in vitro in the presence and absence of fluridone. Cultured kernels, cob tissue, and embryos developed...Full Text Available

International Nuclear Information System (INIS)

I present an exact calculation of free-electron-laser (FEL) eigenmodes (fundamental as well as higher order modes) in the exponential-gain regime. These eigenmodes specify transverse profiles and exponential growth rates of the laser field, and they are self-consistent solutions of the coupled Maxwell-Vlasov equations describing the FEL interaction taking into account the effects due to energy spread, emittance and betatron oscillations of the electron beam, and diffraction and guiding of the laser field. The unperturbed electron distribution is assumed to be of Gaussian shape in four dimensional transverse phase space and in the energy variable, but uniform in longitudinal coordinate. The focusing of the electron beam is assumed to be matched to the natural wiggler focusing in both transverse planes. With these assumptions the eigenvalue problem can be reduced to a numerically manageable integral equation and solved exactly with a ...

Energy Technology Data Exchange (ETDEWEB)

Energy use patterns and utilisation efficiencies in 40 factories producing palm kernel oil (PKO) in southwestern part of Nigeria were studied. The factories were stratified into small, medium and large scale categories based on the mode of operations and production capacities. Questionnaires were administered on the factories to obtain historical data on petrol, diesel and electricity consumption and PKO production outputs for seven years (1998-2004). Energy use efficiency indicators employed include: energy intensity (EI), energy cost per unit product (EC/P), energy ratio (ER), food energy ratio (FER) and percentage oil yield by weight. Results of the study indicated that averagely, 0.58, 0.53 and 0.74 GJ/10{sup 3} l of PKO were needed in the small, medium and large PKO factories, respectively. The average food energy ...

UK PubMed Central (United Kingdom)

Sugar release from the pedicel tissue of maize (Zea mays L.) kernels was studied by removing the distal portion of the kernel and the lower endosperm, followed by replacement of the...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The adoption of a cogenerator integrated system is described. The dry kernel, a woody residue of olive pressing, is produced in very large quantities and could therefore be used in high pressure condensing-extraction team turbines to supply on-site electricity and steam needs. This system is becoming more and more interesting since it produces an excess of electricity which could be sold, e.g. to the electric utility. Such a cogeneration system is discussed in terms of efficiency, capital cost, near-time commercial viability and power-to-fuel costs. The economical analysis is presented for olive press-cake processing plants and can be extrapolated to biomass-based industries having the same characteristics. An energy audit has been carried out on 16 plants. (Author)

British Library Electronic Table of Contents (United Kingdom)

In this article, self-organizing-map-based video object segmentation is proposed, assuming that either Y-quantification or HSV-quantification can be systematically selected. Given a video sequence, the value of the probability density function for each component value is calculated according to a kernel estimation at the first frame. Some areas randomly chosen from the background are then examined, using each component value, to judge whether or not they include the target object. The quantification is determined so that the frequency of occurrence of false extractions can be reduced. The data presented to the maps are generated based on the selected quantification. Experimental results show that the proposed method recognizes the target object well.

International Nuclear Information System (INIS)

We report on the improvement of Critical Dimension (CD) linearity on a photomask by applying the concept of process proximity correction to a laser lithographic process used for fabrication of photomasks. Rule-based Laser Process proximity Correction (LPC) was performed using an automated optical proximity correction tool and we obtained dramatic improvement of CD linearity on a photomask. A study on model-based LPC was executed using a two-Gaussian kernel function and we extracted model parameters for the laser lithographic process by fitting the model-predicted CD linearity data with measured ones. Model-predicted bias values of isolated space (I/S), Arrayed Contact (A/C) and Isolated Contact (I/C) were in good agreement with those obtained by the nonlinear curve-fitting method used for the rule-based LPC.

CERN Document Server

Recently, applying the novel data mining techniques for evaluating enterprise financial distress has received much research alternation. Support Vector Machine (SVM) and back propagation neural (BPN) network has been applied successfully in many areas with excellent generalization results, such as rule extraction, classification and evaluation. In this paper, a model based on SVM with Gaussian RBF kernel is proposed here for enterprise financial distress evaluation. BPN network is considered one of the simplest and are most general methods used for supervised training of multilayered neural network. The comparative results show that through the difference between the performance measures is marginal; SVM gives higher precision and lower error rates.

International Nuclear Information System (INIS)

Dose calculations for radiation arc therapy are traditionally performed by approximating continuous delivery arcs with multiple static beams. For 3D conformal arc treatments, the shape and weight variation per degree is usually small enough to allow arcs to be approximated by static beams separated by 5"0-10"0. But with intensity-modulated arc therapy (IMAT), the variation in shape and dose per degree can be large enough to require a finer angular spacing. With the increase in the number of beams, a deterministic dose calculation method, such as collapsed-cone convolution/superposition, will require proportionally longer computational times, which may not be practical clinically. We propose to use a homegrown Monte Carlo kernel-superposition technique (MCKS) to compute doses for rotational delivery. The IMAT plans were generated with 36 static beams, which were subsequently interpolated into finer angular intervals for dose calculation to mimic ...

International Nuclear Information System (INIS)

IMRT optimization requires a fast yet relatively accurate algorithm to calculate the iteration dose with small memory demand. In this paper, we present a dose calculation algorithm that approaches these goals. By decomposing the infinitesimal pencil beam (IPB) kernel into the central axis (CAX) component and lateral spread function (LSF) and taking the beam's eye view (BEV), we established a non-voxel and non-beamlet-based dose calculation formula. Both LSF and CAX are determined by a commissioning procedure using the collapsed-cone convolution/superposition (CCCS) method as the standard dose engine. The proposed dose calculation involves a 2D convolution of a fluence map with LSF followed by ray tracing based on the CAX lookup table with radiological distance and divergence correction, resulting in complexity of O(N"3) both spatially and temporally. This simple algorithm is orders of magnitude faster than the CCCS method. ...

International Nuclear Information System (INIS)

LLNL is developing the nuclear fusion based Laser Inertial Fusion Energy (LIFE) power plant concept. The baseline design uses a depleted uranium (DU) fission fuel blanket with a flowing molten salt coolant (flibe) that also breeds the tritium needed to sustain the fusion energy source. Indirect drive targets, similar to those that will be demonstrated on the National Ignition Facility (NIF), are ignited at #approx#13 Hz providing a 500 MW fusion source. The DU is in the form of a uranium oxycarbide kernel in modified TRISO-like fuel particles distributed in a carbon matrix forming 2-cm-diameter pebbles. The thermal power is held at 2000 MW by continuously varying the "6Li enrichment in the coolants. There are many options to be considered in the engine design including target yield, U-to-C ratio in the fuel, fission blanket thickness, etc. Here we report results of design variations and compare them in terms of various ...

CERN Document Server

Focusing on Sobolev inequalities and their applications to analysis on manifolds and Ricci flow, "Sobolev Inequalities, Heat Kernels under Ricci Flow, and the Poincare Conjecture" introduces the field of analysis on Riemann manifolds and uses the tools of Sobolev imbedding and heat kernel estimates to study Ricci flows, especially with surgeries. The author explains key ideas, difficult proofs, and important applications in a succinct, accessible, and unified manner. The book first discusses Sobolev inequalities in various settings, including the Euclidean case, the Riemannian case,

British Library Electronic Table of Contents (United Kingdom)

In this study, a two-stage support-vector-regression optimization model (TSOM) is developed for the planning of municipal solid waste (MSW) management in the urban districts of Beijing, China. It represents a new effort to enhance the analysis accuracy in optimizing the MSW management system through coupling the support-vector-regression (SVR) model with an interval-parameter mixed integer linear programming (IMILP). The developed TSOM can not only predict the city's future waste generation amount, but also reflect dynamic, interactive, and uncertain characteristics of the MSW management system. Four kernel functions such as linear kernel, polynomial kernel, radial basis function, and multi-layer perception kernel are chosen based on three quantitative simulation performance criteria [i.e....

UK PubMed Central (United Kingdom)

Kernels of Zea mays on an intact plant accumulate indole-3-acetic acid (IAA) at the rate of 190 ng g-1 fresh weight h-1. Of the IAA synthesized, 97% is in the esterified form and less than 3% remains...Full Text Available

CERN Document Server

In this paper we analyze the Hilbert boundary-value problem of the theory of analytic functions for an $(N+1)$-connected circular domain. An exact series-form solution has already been derived for the case of continuous coefficients. Motivated by the study of the Hall effect in a multiply connected plate we extend these results by examining the case of discontinuous coefficients. The Hilbert problem maps into the Riemann-Hilbert problem for symmetric piece-wise meromorphic functions invariant with respect to a symmetric Schottky group. The solution to this problem is derived in terms of two analogues of the Cauchy kernel, quasiautomorphic and quasimultiplicative kernels. The former kernel is known for any symmetry Schottky group. We prove the existence theorem for the second, quasimultiplicative, kernel for any Schottky group (its series representation is known for the first class groups only). We also ...

Science.gov (United States)

placed on direct energy conversion. This is an advanced technology which is ..... Of the direct energy conversion methods discussed, the only one which may ...

Science.gov (United States)

The article explains the method of selecting the optimum energy for correcting the energy selectivity of tomographic projection and the optimum length of the crystals corresponding to it when the dual energy method in computerized tomography is used. Results of numerical calculations for actual materials and count results are presented.

International Nuclear Information System (INIS)

The true potential energy curve for the x "1#SIGMA#"+ state of BeO has been calculated using the RKRV method. The dissociation energy of the ground state has been estimated to be 5.15 +- 0.05 eV by the curve-fitting method using the three-parameter potential energy function of Lippincott with an RKRV potential energy curve. (author).

Energy Technology Data Exchange (ETDEWEB)

We have developed an energy-extension method of a Bragg curve counter (BCC) at the high-energy end for the measurements of double-differential cross-sections (DDXs) of fragment productions induced by tens of MeV protons. In this method, we estimate the incident energies of the fragments penetrating a BCC on the basis of the energy loss and atomic number (Z). We applied this method to the DDX measurements of the {sup nat}C(p, Li) and {sup nat}C(p, Be) reactions induced by 70 MeV protons. The validity of this method has been confirmed by comparing the DDXs of beryllium with theoretical predictions of the PHITS code and the two-body kinematics. This method improves the energy acceptance of the BCC for light fragments twice as wide as that of a conventional ...

UK PubMed Central (United Kingdom)

In germinating oil palm (Elaeis guineensis var D × P) seedling, an active lipase was present in the shoot but absent from both the kernel and the haustorium. It has an optimum...Full Text Available

UK PubMed Central (United Kingdom)

Indole-3-acetyl-myo-inositol occurs in both the kernel and vegetative shoot of germinating Zea mays seedlings. The effect of a gravitational stimulus on the transport...Full Text Available

CERN Document Server

We construct representation of the Separated Variables (SoV) for the quantum SL(2,R) Heisenberg closed spin chain and obtain the integral representation for the eigenfunctions of the model. We calculate explicitly the Sklyanin measure defining the scalar product in the SoV representation and demonstrate that the language of Feynman diagrams is extremely useful in establishing various properties of the model. The kernel of the unitary transformation to the SoV representation is described by the same "pyramid diagram" as appeared before in the SoV representation for the SL(2,C) spin magnet. We argue that this kernel is given by the product of the Baxter Q-operators projected onto a special reference state.

International Nuclear Information System (INIS)

The action of the Virasoro algebra on integrable hierarchies of non-linear equations and on related objects ('Schroedinger' differential operators) is investigated. The method consists in pushing forward the Virasoro action to the wave function of a hierarchy, and then reconstructing its action on the dressing and Lax operators. This formulation allows one to observe a number of suggestive similarities between the structures involved in the description of the Virasoro algebra on the hierarchies and the structure of conformal field theory on the world-sheet. This includes, in particular, an 'off-shell' hierarchy version of operator products and of the Cauchy kernel. In relation to matrix models, which have been observed to be effectively described by integrable hierarchies subjected to Virasoro constraints, I propose to define general Virasoro-constrained hierarchies also in terms of dressing operators, by certain equations which carry the ...

Energy Technology Data Exchange (ETDEWEB)

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: (1) Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). Note that this includes support for most popular parallel and serial computers. (2) Improved performance for all numerical kernels (e.g., time integrator, nonlinear and linear solvers) through state-of-the-art algorithms and novel techniques. (3) Device models which are specifically tailored to meet Sandia's needs, including some radiation-aware devices (for Sandia users only). (4) Object-oriented code design and implementation using ...

International Nuclear Information System (INIS)

During the last few decades, accuracy in photon and electron radiotherapy has increased substantially. This is partly due to enhanced linear accelerator technology, providing more flexibility in field definition (e.g. the usage of computer-controlled dynamic multileaf collimators), which led to intensity modulated radiotherapy (IMRT). Important improvements have also been made in the treatment planning process, more specifically in the dose calculations. Originally, dose calculations relied heavily on analytic, semi-analytic and empirical algorithms. The more accurate convolution/superposition codes use pre-calculated Monte Carlo dose 'kernels' partly accounting for tissue density heterogeneities. It is generally recognized that the Monte Carlo method is able to increase accuracy even further. Since the second half of the 1990s, several Monte Carlo dose engines for radiotherapy treatment planning have been introduced. To enable the use of a ...

Energy Technology Data Exchange (ETDEWEB)

The methodology of achieving a high power density (HPD, or brake mean effective pressure) direct-injection Diesel engine has been studied, which is directed to using high fuel/air ratio, high-speed and ceramic engine components. Among the main thrust to achieve these engine changes for an advanced Diesel engine is the design of a high injection pressure (HIP) fuel system. During the course of the present study, two Cummins 903 engines mated with a Rutger-built HIP were employed to investigate the engine response to HIP and in-cylinder processes by using the Rutgers high-speed infrared (IR) spectral digital imaging system. Five separate technical publications were prepared to report results obtained from the study. The main findings include: The HIP system permits engine operation at an air/fuel ratio of as rich as 18 to 1 with smoke emission not worse than with the conventional mechanical (low pressure) injection system; A high injection pressure improves HPD of a Diesel engine; A HIP ...

International Nuclear Information System (INIS)

This paper describes the results of a French-Lebanese scientific cooperation, between 2001 and 2005, about 'Rational use of energy in the residential buildings in Lebanon and adaptation of an energy certification procedure'. The aim of this project is to promote the energy efficiency in the existing residential buildings in Lebanon, using an energy certification procedure, and to evaluate the energy certification foresight with prospective methods. The paper first describes an energy investigation in Lebanese residential buildings, and the energy certification procedure. It presents the foresight methodology implemented to identify the key variables and the actors. Finally, the paper exposes the morphological method which allows to elaborate three scenarios of energy performance ...

Science.gov (United States)

Skip to Content Cancer Control and Population Sciences Home Applied Research Home Risk Factor Monitoring and Methods Home Diet Usual Dietary Intakes: Background The NCI Method Details of the NCI Method Food Intakes, US Population, 2001-04 Selected Intakes

CERN Document Server

We consider a family of chiral non-Hermitian Gaussian random matrices in the unitarily invariant symmetry class. The eigenvalue distribution in this model is expressed in terms of Laguerre polynomials in the complex plane. These are orthogonal with respect to a non-Gaussian weight including a modified Bessel function of the second kind, and we give an elementary proof for this. In the large $n$ limit, the eigenvalue statistics at the spectral edge close to the real axis are described by the same family of kernels interpolating between Airy and Poisson that was recently found by one of the authors for the elliptic Ginibre ensemble. We conclude that this scaling limit is universal, appearing for two different non-Hermitian random matrix ensembles with unitary symmetry. As a second result we give an equivalent form for the interpolating Airy kernel in terms of a single real integral, similar to representations for the asymptotic ...

International Nuclear Information System (INIS)

This paper presents a new method for the determination of the energy gap of superconductors. The V/sub max//kT versus #DELTA#/kT curve was calculated from tunneling theory. The maximum voltage in differential conductance V/sub max/ was measured from the electron tunneling spectrum. From V/sub max//kT and the curve, one can easily calculate the energy gap value #DELTA#. This method is simple, and the accuracy almost approaches that of the curve-fitting method.

International Nuclear Information System (INIS)

We calculated the energies of asymmetric nuclear matter at zero and finite temperatures with the cluster variational method. At zero temperature, the expectation value of the two-body Hamiltonian composed of the kinetic energies and the AV18 two-body forces is calculated with the Jastrow wave function in the two-body cluster approximation. The obtained two-body energy is in good agreement with the result with the Fermi Hypernetted Chain (FHNC) calculation by Akmal et al. The energy caused by the UIX three-body forces is treated somewhat phenomenologically so that the total energy reproduces the empirical saturation point. Furthermore, the parameters included in the three-body energy are readjusted so that the Thomas-Fermi (TF) calculations with use of the obtained energy of nuclear matter reproduce the gross feature of ...

Energy Technology Data Exchange (ETDEWEB)

The defects localization in power cables follows several steps: identification, pre-localization and precise localization. Pre-localization methods, other than echo-metry, are presented first: bridge methods, particular case of low voltage networks, future perspectives. Then, the precise localization methods are described: magneto-acoustic method, audible frequencies method. The particular case of underwater and high-voltage cables is considered too (oil and gas leaks detection). (J.S.)

International Nuclear Information System (INIS)

The electronic structure of octahedral metal atom clusters Me_6 of 3d, 4d, and 5d transition metal atoms (V, Cr; Nb, Mo; Ta, W) has been calculated applying two different quantum-chemical approximation methods (Extended Hueckel (EH) method; SW-Xsub(alpha) method). Equilibrium structures, energy level schemes, Fermi energies and band widths as well as densities of states of clusters are discussed in detail.

Energy Technology Data Exchange (ETDEWEB)

Energy savings performance contracting (ESPC) is now receiving greater attention as a means of implementing large-scale energy conservation projects in housing. Opportunities for such projects exist for military housing, federally subsidized low-income housing, and planned communities (condominiums, townhomes, senior centers), to name a few. Accurate prior (to construction) estimates of the energy savings in these projects reduce risk, decrease financing costs, and help avoid post-construction disputes over performance contract baseline adjustments. This paper demonstrates an improved method of estimating energy savings before construction takes place. Using an engineering model calibrated to pre-construction energy-use data collected in the field, this method is able to predict actual energy savings to a high degree of ...

Energy Technology Data Exchange (ETDEWEB)

Renewable energy systems, such as photovoltaic and wind-turbine energy systems, are considered to be environmentally sound from the viewpoint of carbon-dioxide emissions and resource depletion. The cost of energy supplied from renewable energy systems is higher than that of conventional fossil-fuel systems, and this hinders the wider spread of renewable energy systems. Global environmental problems, however, are becoming more obvious. There is a movement to defray the additional cost of electricity generated in environmentally-sound processes. In this paper, we report the results of a survey using the contingent valuation method (CVM) of the willingness of Japanese households to pay more, in the form of a flat monthly surcharge, for renewable energy. The median value of willingness to pay for renewable energy by Japanese ...

Energy Technology Data Exchange (ETDEWEB)

The IEA has identified energy efficiency as essential to achieving a sustainable energy future. In order to improve energy efficiency in industry one of the priority areas for further action is the promotion of more and higher quality energy management (EM) activity. However, there are significant gaps in the current implementation of EM. One method of bridging these gaps would be the creation of an EM Action NetworK (EMAK) to bring practical support to energy managers, connect energy managers to energy policy makers, and interconnect these networks globally. The paper describes possible aims, activities, scope, structure, timelines and approaches related to EMAK and looks at specific tasks that would be important in the set-up and implementation.

Energy Technology Data Exchange (ETDEWEB)

Geoinformatics, of which remote sensing, global positioning system and geographical information system are kernel components, has developed rapidly and become applicable in the last ten years. In this paper, the recent development and advantages of geoinformatics are introduced; some achievements and understanding in applications for environmental protection in mining areas are also described. 7 refs., 5 figs., 1 tab.

International Nuclear Information System (INIS)

The RKR potential energy curves are constructed for the ground states of diatomic hafnium oxide and thorium oxide. Using Lippincott and Hulburt-Hirschfelder potential function the dissociation energies are estimated by curve fitting method. The H-H potential function was found to give a better fit in both cases. The dissociation energies of hafnium oxide and thorium oxide are estimated as 9.04 #+-# 0.02 eV and 10.34 #+-# 0.01 eV respectively. (author).

Energy Technology Data Exchange (ETDEWEB)

Drying fine coal by microwaves is now being considered as a viable option by some coal producers. The interest in microwaves is due to problems encountered with current thermal or hot-air drying methods. The technical feasibility of drying minus 5mm coal fines by microwaves was demonstrated using pilot-scale continuous processing system. Results showed that water absorbs microwave energy significantly; but coal does not. Secondly, microwave energy heats only the water, unlike existing drying methods, which heat both water and coal. Finally, the method was found to be energy efficient and minimised the generation of dust.

International Nuclear Information System (INIS)

A calculation method of the X-ray radiation dose (energy of gamma- radiation remains in the range of energies where the mechanism of photoelectric absorption is the prevailing one) absorbed in the absorbers of final thickness is suggested. Calculations of resorption of secondary radiation (characteristic fluorescences) in the substance and kinetic energy of photoelectrons caused by this resorption (it would be enough to consider one or two hard series) are presented. Calculation of the spectrum of photoelectron energy yield in TeInSe_2 monocrystal for 0.1-0.5 A range of X-ray radiation is conducted by the developed methods.

Energy Technology Data Exchange (ETDEWEB)

Energy and exergy studies were conducted in an orange juice manufacturing industry in Nigeria to determine the energy consumption pattern and methods of energy optimization in the company. An adaptation of the process analysis method of energy accounting was used to evaluate the energy requirement for each of the eight defined unit operations. The types of energy used in the manufacturing of orange juice were electrical, steam and manual with the respective proportions of 18.51%, 80.91% and 0.58% of the total energy. It was estimated that an average energy intensity of 1.12 MJ/kg was required for the manufacturing of orange juice. The most energy intensive operation was identified as the pasteurizer followed by packaging unit with energy ...

Energy Technology Data Exchange (ETDEWEB)

Energy consumption of black coal mines in Poland and methods for energy conservation are evaluated. Organizational models of energy management in underground coal mining are discussed. Tasks for dispatcher service for energy consumption control in a coal mine are analyzed: control of energy supplies, control of energy consumption, evaluation of electrical failures and reliability of protection systems, recording accidents and analyzing their causes, optimization of power systems in underground mines. Problems associated with control of energy consumption in a coal mine with mechanized systems for coal mining and use of computerized control systems are discussed. Recommendations for reucing energy consumption in underground coal mining are made. 4 references.

Energy Technology Data Exchange (ETDEWEB)

The paper describes the different methods, used in the MAGIC experiment, to unfold experimental energy distributions of cosmic ray particles ({gamma}-rays). Questions and problems related to the unfolding are discussed. Various procedures are proposed which can help to make the unfolding robust and reliable. The different methods and procedures are implemented in the MAGIC software and are used in most of the analyses.

Energy Technology Data Exchange (ETDEWEB)

Cost-time management methods have been developed by Westinghouse to examine business applications from a cost-time perspective. The initial application of cost-time management within Westinghouse was targeted at reducing cycle time in the manufacturing sector. As a result of the tremendous success of reduced cycle time in manufacturing, Westinghouse initiated application of the management technique to Environmental Restoration activities at its Government Owned Contractor Operated facilities. The Westinghouse initiative was proposed in support of the Department of Energy`s goals for cost effective Environmental Restoration activities. This paper describes the application of the cost-time method to Environmental Restoration work currently being performed at the Idaho National Engineering Laboratory (INEL) for the Department of Energy (DOE) by Westinghouse Idaho Nuclear Company (WINCO).

Energy Technology Data Exchange (ETDEWEB)

The paper industry needs alternative waste disposal methods rather than dumping sites. The combustion properties of these waste materials make them suitable for thermal disposal. A process has been developed in which the waste materials are burnt on an oscillating bar grate without supplying external energy. Electrical energy and process steam are generated while small amounts of a sintered slag remain behind. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Depth dose distributions for protons in the energy range from 2 to 600 MeV have been calculated by Monte Carlo and analytical methods. The dependence on energy of Maximum Dose Equivalent (MDE), quality factor and isotropic factor recommended for practical use are presented. The problems connected with regulation of maximum permissible proton fluxes are discussed. (author).

Energy Technology Data Exchange (ETDEWEB)

The electronic structure of small niobium clusters Nb/sub n/ (n = 2, 4, 6, 9) has been calculated applying two different quantum-chemical approximation methods (Extended Hueckel (EH) method; SW-X/sub alpha/ method). It was found that both the methods led to the same results concerning equilibrium structures, energy level schemes, Fermi energies and band widths as well as the densities of states of the clusters. In solving solid state problems of transition metals with the aid of the cluster model a better adaptation of the EH method should be expected by adjusting the EH parameters to the SW-X/sub alpha/ results.

International Nuclear Information System (INIS)

We present a method for obtaining the quasi-exact solutions of the Rabi Hamiltonian in the framework of the asymptotic iteration method (AIM). The energy eigenvalues, the eigenfunctions and the associated Bender-Dunne orthogonal polynomials are deduced. We show (i) that orthogonal polynomials are generated from the upper limit (i.e., truncation limit) of polynomial solutions deduced from AIM, and (ii) prove to have nonpositive norm. (authors)

Energy Technology Data Exchange (ETDEWEB)

The assets that Citizen Potawatomi Nation holds were evaluated to help define the strengths and weaknesses to be used in pursuing economic prosperity. With this baseline assessment, a Planning Team will create a vision for the tribe to integrate into long-term energy and business strategies. Identification of energy efficiency devices, systems and technologies was made, and an estimation of cost benefits of the more promising ideas is submitted for possible inclusion into the final energy plan. Multiple energy resources and sources were identified and their attributes were assessed to determine the appropriateness of each. Methods of saving energy were evaluated and reported on and potential revenue-generating sources that specifically fit the tribe were identified and reported. A primary goal is to create long-term energy strategies to ...

Energy Technology Data Exchange (ETDEWEB)

New partial differential equations (PDEs) for the full order weak schemes of the Langevin simulations are formulated. They are solved recursively in full order series solutions with respect to {radical}(t) (the full order weak Taylor schemes). Arbitrariness involved in the solutions is analyzed and clarified in detail. Specific solutions within some orders are presented as examples of the weak Taylor schemes. These PDEs and their solutions will serve for further developments of efficient higher order Runge-Kutta-like schemes. The similar formulation is possible for the imaginary time Hamiltonian evolution kernels as well. (orig.). 9 refs.

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to test a large sample of different coronary artery stents using four image reconstruction approaches with respect to lumen visualization, lumen attenuation, and image noise in 64-slice multidetector-row computed tomography (MDCT) in vitro and to provide a catalogue of currently used coronary artery stents when imaged with state-of the-art MDCT. We examined 68 different coronary artery stents (57 stainless steel, four cobalt-chromium, one cobalt-alloy, two nitinol, four tantalum) in a coronary artery phantom (vessel diameter 3 mm, intravascular attenuation 250 HU, extravascular density -70). Stents were imaged in axial orientation with standard parameters: 32x0.6 collimation, pitch 0.24, 680 mAs, 120 kV, rotation time 0.37 s. Four different image reconstructions were obtained with varying convolution kernels and section thicknesses: (1) soft, 0.6 mm, (2) soft, 0.75, (3) medium soft, 0.6, and (4) stent-optimized sharp, 0.6. To evaluate ...

International Nuclear Information System (INIS)

Thinning specimens to electron transparency for electron microscopy analysis can be done by conventional (2-4 kV) argon ion milling or focused ion beam (FIB) lift-out techniques. Both these methods tend to leave 'mottling' visible on thin specimen areas, and this is believed to be surface damage caused by ion implantation and amorphisation. A low energy (250-500 V) Argon ion polish has been shown to greatly improve specimen quality for crystalline silicon samples. Here we investigate the preparation of technologically important materials for nanoanalysis using conventional and lift-out methods followed by a low energy polish in a GentleMill"T"M low energy ion mill. We use a low energy, low angle (6-8 deg.) ion beam to remove the surface damage from previous processing steps. We assess this method for the preparation of technologically ...

International Nuclear Information System (INIS)

We studied the influence of alloying on the structural and electronic properties of the unrelaxed and relaxed Si_1_-_yC_y random alloys by means of ab initio theoretical calculations using two methods: (i) a supercell approach in connection with the plane-wave pseudopotential method; (ii) the full-potential augmented plane-wave plus local orbitals (APW+lo) method. The first method is used to obtain the relaxed atomic structure. The relaxed atomic positions obtained by pseudopotential calculations were used to calculate the band structure via the second method. The local density approximation was used for the exchange and correlation energy density functional. We investigated the lattice parameters and band gap energies. We found that a quite smaller gap appears in the neighborhood of y=0.03125 concentration of C atoms. The band gap shows a ...

International Nuclear Information System (INIS)

The principal mathematical tools frequently available for calculations in Nuclear Engineering, including coupled neutron-gamma radiations shielding problems, involve the full Transport Theory or the Monte Carlo techniques. The Multigroup Albedo Method applied to shieldings is characterized by following the radiations through distinct layers of materials, allowing the determination of the neutron and gamma fractions reflected from, transmitted through and absorbed in the irradiated media when a neutronic stream hits the first layer of material, independently of flux calculations. Then, the method is a complementary tool of great didactic value due to its clarity and simplicity in solving neutron and/or gamma shielding problems. The outstanding results achieved in previous works motivated the elaboration and the development of this study that is presented in this dissertation. The radiation balance resulting from the incidence of a neutronic ...

Energy Technology Data Exchange (ETDEWEB)

A first-principles quasiparticle approach to the electronic excitation energies in crystals and at surfaces is described. The quasiparticle energies are calculated within the GW approximation for comparison with photoemission and other spectroscopic experiments. Applications of the method to bulk semiconductors and the Si(111)2[times]l, Ge(111)2[times]l. and H/Si(III) surfaces are presented. In both cases, significant self-energy corrections arising from many-electron effects to the excitation energies are found. Using atomic positions from total energy minimization, the calculated excitation energies explain quantitatively the experimental spectra. This approach thus provides an ab initio means for analyzing and predicting results from spectroscopic probes.

Energy Technology Data Exchange (ETDEWEB)

This book applies the Los Alamos Solar Load Ratio (SLR) method to the design of passive solar heating systems, with an emphasis on the average annual heating energy consumption. Recommendations are given on minimizing heating energy consumption by appropriate choices of conservation level and solar system parameters. Analytical methods and supporting tables are presented which enable simple, fast estimates of the heating energy consumption as part of the design process. Topics considered include SLR correlations, the load collector ratio (LCR) method, sensitivity data, cooling considerations, conservation formulas, design procedure, life-cycle costs, high-mass direct gain buildings, low-mass sun-tempered buildings, sunspaces, off-reference night insulation, correlation equations, and mixed systems.

International Nuclear Information System (INIS)

An accurate neutronics calculation of a local thermal environment within a fast reactor presents a major challenge. A method was previously described that used Monte Carlo techniques within a macrocell to make accurate and reasonably efficient design calculations for such an environment. This method is now being further optimized for the calculation of "2"3"8Pu production in the Fast Flux Test Facility (FFTF). Here, it is not only important to determine the "2"3"8Pu production from neutron capture in "2"3"7Np, but also to calculate the production of the contamination isotope "2"3"6Pu from high-energy (n,2n) and (#gamma#,n) reactions. The power of the Monte Carlo method to automatically include geometry and energy self-shielding is retained by optimization using fission neutron source biasing in both space and energy.

Energy Technology Data Exchange (ETDEWEB)

A practical method to determine the ionic diffusion coefficient and activation energy by using quasielastic light scattering (QELS) is presented. It is shown that a temperature dependence curve of the QELS intensity at a fixed frequency can be well fitted by Jonscher's formula and that the diffusion parameters can be obtained from this curve fitting. This method is successfully applied not only to crystals with high optical quality, as reported earlier, but also to opaque ceramics, which are more important than the crystals from a practical point of view. The composition dependence of the ionic diffusion coefficient is studied in sintered YbSZ to show the usefulness of this method.

Energy Technology Data Exchange (ETDEWEB)

We consider low-energy nucleons at next-to-next-to-leading order in lattice chiral effective field theory. Three-body interactions first appear at this order, and we discuss several methods for determining three-body interaction coefficients on the lattice. We compute the energy of the triton and low-energy neutron-deuteron scattering phase shifts in the spin-doublet and spin-quartet channels using Luescher's finite-volume method. In the four-nucleon system we calculate the energy of the {alpha}-particle using auxiliary fields and projection Monte Carlo. (orig.)

British Library Electronic Table of Contents (United Kingdom)

SummaryThis paper examines the sensitivity and uncertainty of evaporation estimates from Nasser Lake, south of Egypt using data collected at the floating station Raft, 2km upstream of the Aswan High Dam, and 12 evaporation models. Based on their approach the evaporation models were ranked in five classes, respectively the Bowen ratio energy budget (BREB) approach, three energy-aerodynamic based methods, a mass transfer method, two temperature and five solar radiation-temperature approaches. State dependent parameter models were used to estimate the sensitivity indices of the different evaporation estimation methods at daily and monthly frequencies. A drastic reduction in the cost of the sensitivity analysis was obtained when coupled with efficient sampling methods, producing quasi-Monte Ca...

Energy Technology Data Exchange (ETDEWEB)

Hoogenstraaten's heating rate method has generally been considered as a reliable method for determining thermoluminescence trapping parameters of first order glow peaks. However, experience has shown that in some cases the deviation between the heating rate method and glow curve fitting method can be quite significant (considering only the linear part of the heating rate plot, of course). In this study it is shown that one of the main reasons for this deviation can be a systematic increase of a temperature lag between the measured and real temperature of the sample with increasing heating rate. It appears that this systematic increase of the temperature lag affects the method in the range of low heating rates (linear part of the heating rates plots) more than has been previously realised. The effect of the temperature lag on Hoogenstraaten's heating rate ...

Science.gov (United States)

Technologies for materials, processes, and manufacturing that will provide safe, .... advanced energy conversion techniques, and pulsed inductive and ... duration antimatter storage and transportation, and methods for utilizing ...... EVA systems can be found in the EVA Technology Roadmap of the EVA Project Plan. ...

Science.gov (United States)

The metal-semiconductor solar cell is a potential candidate for converting solar energy to electrical energy for space and terrestrial application. In this paper, a method for obtaining parameters of practical antireflection (AR) coatings for the metal-semiconductor solar cells is given. This method utilizes the measured equivalent index of refraction obtained from ellipsometry, since the surface to be AR coated has a multilayer structure. Both the experimental results and theoretical calculations of optical parameters for Ta/sub 2/O/sub 5/ AR coatings on Au-GaAs and Au-GaAs/sub 0.78/P/sub 0.22/ solar cells are presented for comparison. (AIP)

International Nuclear Information System (INIS)

Bases of the algorithm for assessing the reinforcement status in reinforced concrete products by gamma-absorption method are presented. Analytical equations are obtained for estimation of error of the parameter characterizing the degree of reinforcement destruction. It is recommended to use high-energy Bremsstrahlung sources-betatrons of 4-10 MeV maximum energy for testing products of 500-600 mm thick. Linear radiation attenuation factor (LAF) of concrete in estimated equation is replaced by effective LAF of concrete, and LAF of reinforcement and corrosion materials - by differential LAF. Corresponding LAF of nonevident form in the algorithm is assessed by the results of processing of direct-shadow radiographs of defectometers

International Nuclear Information System (INIS)

180 deg magnet chamber is used in Folded Tandem Ion Accelerator for passage and 180 deg bending of ion beam. The chamber is placed between 180 deg terminal magnet (Electro-magnet), which is used for bending, and analysing the beams. Magnet with a particular magnetic field strength bends ions of only specified mass energy product through a precise path. There is also a space limitation in the direction of magnetic field. Both of them require the magnet chamber to be of a close tolerance. Accuracy of center distance between inlet and outlet port of the magnet chamber has to be at par with the concentricity of high energy and low energy beam line. To achieve this we started the fabrication of magnet chamber by following two methods: a) Circular rolling and bending of rectangular tube for 180 deg sector of magnet chamber b) Machining 180 deg sector in two half and welding. By first ...

British Library Electronic Table of Contents (United Kingdom)

A range of new nanomaterials to replace the active materials in lithium ion batteries are currently being studied and employed in an attempt to overcome various performance limitations of previous technologies. Nanomaterial production and manufacturing techniques appear to fit into a general trend towards more energy intensive production methods for high-tech goods. This does not necessarily imply an increase in lifecycle energy use; artefacts that consume or transform energy during use could possibly regain this increased initial input via increased efficiency in use. In particular, this paper highlights that larger gains could be possible if the artefact in question allows a given service to be provided via an alternative and more efficient system entirely.The lifecycle energy efficienci...

CERN Document Server

The pair-specific ground state energy of Newtonian N-body systems grows monotonically in N. This furnishes a whole family of simple new tests for minimality of putative ground state energies obtained through computer experiments. Inspection of several publically available lists of such computer-experimentally obtained putative ground state energies has yielded several dozen instances which failed (at least) one of these tests. Although the correct ground state energy is not revealed by this method, it does yield a better upper bound on it than the experimentally found value whenever the latter fails a monotonicity test. The surveyed N-body systems include in particular N point charges with 2- or 3-dimensional Coulomb pair interactions, placed either on the unit 2-sphere or on a 2-torus (a.k.a. Thomson, Fekete, or Riesz problems).

Science.gov (United States)

We report here a new approach to introduce the effect of chemisorption in the Monte-Carlo simulation procedure for studying the segregation behaviour in bimetallic nanoparticles at low pressures. A coordination-dependent pair interaction energy is constructed in terms of partial bond energies and the exchange energy where the partial bond energy can be empirically calculated from the experimental values of dimer energy, the pressure-dependent surface energy and the bulk cohesive energy of the constituent metals. The advantage of this procedure is the ability to estimate the pressure-dependent surface composition of the nanoparticles. The method has been applied to oxygen-adsorbed Pd-Ag systems; and it is found that while Ag segregate in clean particles, at higher oxygen pressures Pd atoms segregate to the surface. The ...

International Nuclear Information System (INIS)

For the Convolution, Superposition and Monte Carlo methods, energy spectrum data is an essential parameter. Especially, by using Monte Carlo method, if the adequate properties of electrons are set, complex energy spectrum data can be calculated by simple input. However, adjustment of the property of electrons incident on the target of linear accelerator is time-consuming procedure. To cover the difference of many accelerators, it is important how we obtain accurate energy spectrum by simple methods. Especially, the total accuracy of dose calculation depends on the agreement of measured and calculated percentage depth dose (PDD) and off-axis ratio (OAR). Thus, a simple method for the determination of the simulation parameters was considered. To reduce the adjustment procedure, we selected values of important three parameters, which were the ...

Energy Technology Data Exchange (ETDEWEB)

Effect of ultrasonic-wave irradiation on the Mn-Zn ferrite powder suspension prepared by solid-state reaction and alcoholic dehydration methods was investigated. Size, distribution, and morphology of the powders prepared at different temperatures were examined, as a function of irradiation time. It was observed that the powders were reduced in size by ultrasonic energy through distinct routes. 8 refs., 7 figs., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

An algebraic formulation of the electromagnetic field in which various quantization procedures can be described was chosen to discuss perturbation calculations. It is shown that the Feynman rules and the second order calculation of the self-energy of the electron can be developed on the basis of the Fermi method of quantization. The algebraic approach clarifies the problems in defining the vacuum and other states which are associated with calculations in terms of field algebra operators. It is demonstrated that the vacuum state defined on the field algebra by Schwinger leads to incorrect results in the self-energy calculation.

Energy Technology Data Exchange (ETDEWEB)

This paper describes a proposed set of guidelines for analyzing the energy savings achieved by a package of retrofits or an extensive rehabilitation of an existing home. It also describes certain field test and audit methods that can help establish accurate building system performance characteristics that are needed for a meaningful simulation of whole-house energy use. Several sets of default efficiency values have been developed for older appliances that cannot be easily tested and for which published specifications are not readily available. These proposed analysis procedures are documented more comprehensively in NREL Technical Report TP-550-38238.

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy, Division of Electric Energy Systems, has undertaken to identify the environmental issues and potential impacts associated with the installation of underground electric power transmission systems. This study reports the results of investigations into the advanced cable technologies being considered for future underground applications, as part of the development oriented research program of the Division of Electric Energy Systems. While the technology involves a high level of sophistication, there are relatively few impacts to the environment that are potentially significant, and of these none are inherently non-mitigable. Route planning, system design, and methods of construction and accident response can be pursued in order to minimize impacts where strict constraints are appropriate.

Energy Technology Data Exchange (ETDEWEB)

Sigma 1) examines ways to reduce the number of breakdowns of pressure-regulating stations and to minimize the energy consumed in warming the gas, 2) determines the optimal gas temperatures upstream from the pressure reduction, and 3) shows the dependence of energy consumption upon the water dewpoint. The method of calculating the optimal input temperature relies on Mollier's diagram. Tables and nomographs for natural gas and water dewpoint at 19/sup 0/F and 580 psi (-7/sup 0/C and 4 MPa) are useful in achieving the desired gas temperatures. Heating the regulators' control valves is important.

Energy Technology Data Exchange (ETDEWEB)

Many mining regions in the United States contain extensive areas of flooded underground mines. The water within these mines represents a significant and widespread opportunity for extracting low-grade, geothermal energy. Based on current energy prices, geothermal heat pump systems using mine water could reduce the annual costs for heating to over 70 percent compared to conventional heating methods (natural gas or heating oil). These same systems could reduce annual cooling costs by up to 50 percent over standard air conditioning in many areas of the country. (Formatted full-text version is released by permission of publisher)

Energy Technology Data Exchange (ETDEWEB)

Because of good thermal insulation of advanced energetic buildings and their good airtightness the air hygiene is insufficient. A normal ventilation behaviour by window opening consumes too much heating energy. A calculation method is shown taking into account a required air change number, flow rate and indoor air quality as thermal comfort in the rooms occupied by different number of persons. (GL)

International Nuclear Information System (INIS)

In-situ compaction method is an alternative technology for the construction of a buffer at HLW final disposal. Understanding of the compaction characteristics of the proposed material is important for this method of construction. In this report, paying attention to the relation between compaction energy and the achieved maximum dry density, dynamic compaction characteristic of bentonite and silica sand mixture material is examined. (author)

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)

The application of various signal processing methods to extract energy storage information from plasma diamagnetism sensors occurring during physics experiments on the Tandom Mirror Experiment-Upgrade (TMX-U) is discussed. We show how these processing techniques can be used to decrease the uncertainty in the corresponding sensor measurements. The algorithms suggested are implemented using SIG, an interactive signal processing package developed at LLNL.

Energy Technology Data Exchange (ETDEWEB)

In this paper, a new design methodology for determining the size, location, type and number of capacitors to be placed on a radial distribution system is presented. The objective is to minimize the peak power losses and the energy losses in the distribution system considering the capacitor cost. A sensitivity analysis based method is used to select the candidate locations for the capacitors. A new optimization method using a Genetic Algorithm is proposed to determine the optimal selection of capacitors. Test results have been presented along with the discussion of the algorithm.

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

Energy Technology Data Exchange (ETDEWEB)

This report deals with the selection of a data communication system for a remote metering system. It covers the following three types of systems: fiber optic, telephone line, and radio packet. It provides a methodology for selecting a communication system for a given remote metering system and a method for comparing costs.

Energy Technology Data Exchange (ETDEWEB)

A new method named 'Bragg curve spectroscopy', based on the Bragg curve of the heavy ion being stopped in a gaseous ionization chamber, has been developed for identifying the particle and measuring its energy. The design of such a chamber and the experience obtained with chamber using various kinds of fast heavy ions are described. In conclusion, several problems to be solved in this method are pointed out.

Energy Technology Data Exchange (ETDEWEB)

In ab initio molecular dynamics, whenever information about the potential energy surface is needed for integrating the equations of motion, it is computed 'on the fly' using electronic structure calculations. For Born-Oppenheimer methods, the electronic structure calculations are converged, whereas in the extended Lagrangian approach the electronic structure is propagated along with the nuclei. Some recent advances for both approaches are discussed.

International Nuclear Information System (INIS)

The most important commercialized methods of attenuation correction in SPECT are based on attenuation coefficient map from a transmission imaging method. The transmission imaging system can be the linear source of radioelement or a X-ray CT system. The image of transmission imaging system is not useful unless to replacement of the attenuation coefficient or CT number with the attenuation coefficient in SPECT energy. In this paper we essay to evaluate the validity and estimate the error of the most used method of this transformation. The final result shows that the methods which use a linear or multi-linear curve accept a error in their estimation. The value of mA is not important but the patient thickness is very important and it can introduce a error more than 10 percent in the final result.

International Nuclear Information System (INIS)

Based on the X-ray crystallographic data of Tc-complexes for brain imaging agents, geometry optimizations in vacuo of TcO-BAT, TcO-MAMA, TcO-L, L-ECD, TcN-BAT and TcN-L, L-ECD complexes are performed with Hartree-Fock method and LANL 2 DZ basis set of G98W program. Then solvation free energy for each Tc-complex mentioned above in water is calculated by polarizable continuum method (PCM) including models of CPCM and IEFPCM. The results show that solvation free energy of Tc-complex is not only an indicator of lipophilicity but also one of the important factors that influence the brain uptake

British Library Electronic Table of Contents (United Kingdom)

In this paper we introduce free energy-based methods to constrain mutual information maximization, developed to realize competitive learning. The new method is introduced to simplify the computational procedures of mutual information and to improve the fidelity of representation and to stabilize learning. First, the free energy is effective in simplifying the computation procedures of mutual information because we need not directly compute mutual information, which needs heavy computation, but only deals with partition functions. With partition functions, computational complexity is significantly reduced. Second, fidelity to input patterns can be improved because training errors between input patterns and connection weights are implicitly incorporated. This means that mutual information is...

Energy Technology Data Exchange (ETDEWEB)

In robotics inverse dynamics is a standard control concept for highly nonlinear multibody systems. It is shown, however, that inverse dynamics results in a high energy demand. Therefore, linear energy efficient state feedback controllers are designed in a way that a performance index representing the energy consumption is minimized. At the same time inequality constraints such as control error and limited input variables have to be met. For the control design an analytical solution by pole placement is presented as well as a numerical controller optimization. This control design includes small motions in the neighborhood of the operating point. Then, linear controllers are tested with respect to control error and energy consumption when undergoing large displacement motion. It is shown that linear state feedback can only save energy if large control errors are accepted. Therefore, ...

International Nuclear Information System (INIS)

Energy balances are analysed from a life-cycle perspective for biogas systems based on 8 different raw materials. The analysis is based on published data and relates to Swedish conditions. The results show that the energy input into biogas systems (i.e. large-scale biogas plants) overall corresponds to 20-40% (on average approximately 30%) of the energy content in the biogas produced. The net energy output turns negative when transport distances exceed approximately 200 km (manure), or up to 700 km (slaughterhouse waste). Large variations exist in energy efficiency among the biogas systems studied. These variations depend both on the properties of the raw materials studied and on the system design and allocation methods chosen. The net energy output from biogas systems based on raw materials that have high water content and low biogas yield ...

Science.gov (United States)

A new approach of gear fault diagnosis based on continuous wavelet transform is presented. Continuous wavelet transform can provide a finer scale resolution than orthogonal wavelet transform. It is more suitable for extracting mechanical fault information. In this paper, the concept of time-averaged wavelet spectrum (TAWS) based on Morlet continuous wavelet transform is proposed. Two fault diagnosis methods named spectrum comparison method (SCM) and feature energy method (FEM) based on TAWS are established. The results of the application to gearbox gear fault diagnosis show that TAWS can effectively extract gear fault information. The feature energy of the TAWS features the gear fault advancement very well and is conically proportional to the gear fault advancement.

Energy Technology Data Exchange (ETDEWEB)

An approximate solution was proposed in which a sensitivity analysis by the storage and release of heat was performed for the subject issues and in which an operating method was thereby determined for the equipment constituting the system by means of a linear programming. Accordingly, a heat storage type energy supply system for a district cooling and heating was taken up as a concrete object to be examined. This system consisted of a gas turbine generator, initial power receiving equipment, gas boiler, electric heat pump for ice heat storage, cooling tower, heat exchanger, steam absorbing refrigerating machine, ice heat storage tank, cold and warm water heat storage tank, etc. As a result of comparison between the proposed method and the resolving method, the former showed -0.92 to 2.58% in the increase in the operating cost compared with the latter. A case where the operating cost of the resolving ...

International Nuclear Information System (INIS)

To make the doubly labelled water method for determining energy expenditure more applicable in a free-living population, collection of a single daily urine or breath sample would have advantages compared to a 24-hr urine collection. Coward et al. reported the use of a single daily urine sample. In the previously described study, a single urine collection and a fasting morning breath sample were collected from four men during two 21-day periods (fall, F, spring, S) while maintaining their body wts. on controlled diets (20% calories from protein, 40% from fat, 60% from CHO [F]; 20% protein, 20% fat, 60% CHO [S]). Urine and breath samples were analyzed to determine disappearance rates of D and "1"8O for up to 21 days. Values were compared with metabolizable energy intake levels (EI), with or without corrections for estimated changes in body composition assessed by several methods. Preliminary evaluations ...

International Nuclear Information System (INIS)

The first-order relativistic correction to the kinetic energy of an electron, the mass-velocity term, is not bounded from below. It can, therefore, not be used within a variational framework. To overcome this deficiency we developed a method to include the entire relativistic kinetic energy #sq root#(p"2c"2+m_0"2c"4)-m_0c"2 in a spline-augmented plane-wave band calculation. The first results for silver are quite promising, especially for d and p states: The analysis of the energies of the core states as well as of the valence band structure suggests that the energies of d bands are reproduced within 1 mRy. However, the combination of the relativistic kinetic energy with the Darwin term leads to energies which are too low for s-like valence states by 10 mRy. Therefore, the s and d valence band complex is spread out and the Fermi level is ...

International Nuclear Information System (INIS)

Energy band diagrams of LaCuOCh (Ch = S, Se and Te) were calculated by a full-potential linearized augmented plane-wave method. The calculations, based on the local density approximation with/without an on-site Coulomb repulsion parameter, were to examine the energy levels of La 4f states. The results of the calculations showed that the on-site correlation parameter is necessary for evaluating the energy levels of La 4f states appropriately. The calculations for LaCuOCh with the on-site correlation parameter revealed that LaCuOS and LaCuOSe have almost the same energy band structure with a direct allowed-type band gap, while LaCuOTe has significantly different conduction band structure that exhibits an indirect-type band gap. This difference in electronic structure between LaCuOCh (Ch = S, Se and Te) is consistent with the observed optical properties of these materials.

British Library Electronic Table of Contents (United Kingdom)

Local communities in southern Africa derive many benefits from marula [Sclerocarya birrea (A. Rich.) Hochst. subsp. caffra (Sond.) Kokwaro]. These include the contribution of this species towards health, nutrition, food security and conservation by sharing local skills and knowledge related to it. Marula fruits can be eaten fresh, squeezed to make juice, brewed in traditional beer or used to make jam and jelly. The kernels are also edible and can be pressed to extract oil for cooking and cosmetics, i.e., for skin and hair application. The bark, roots, seeds and leaves are exploited for traditional medicinal purposes. Marula has acquired significant commercial value since its fruits and other products have entered local, regional and international trade in southern Africa. To diversify frui...

CERN Document Server

We consider various modifications of the Weyl-Moyal star-product, in order to obtain a finite range of nonlocality. The basic requirements are to preserve the commutation relations of the coordinates as well as the associativity of the new product. We show that a modification of the differential representation of the Weyl-Moyal star-product by an exponential function of derivatives will not lead to a finite range of nonlocality. We also modify the integral kernel of the star-product introducing a Gaussian damping, but find a nonassociative product which remains infinitely nonlocal. We are therefore led to propose that the Weyl-Moyal product should be modified by a cutoff like function, in order to remove the infinite nonlocality of the product. We provide such a product, but it appears that one has to abandon the possibility of analytic calculation with the new product.

British Library Electronic Table of Contents (United Kingdom)

Orthogonal frequency division multiplexing (OFDM) can fully use the frequency band and transmit data at high speeds. The ADSP-TS101 is a high performance digital signal processor (DSP) with good properties that include parallel processing and a high speed. Aimed at the real-time processing requirement of the OFDM algorithm, an underwater acoustic communication system with real-time processing capability is carried out. The system is mainly composed of multiple ADSP-TS101s, a multi-channel synchronous sample module and a field programmable gate array (FPGA) chip. The multiprocessor structure is made up of a cluster/data flow associated multiprocessing parallel processing structure as the operation kernel, and a multi-channel synchronous sample module is designed to realize no phase warp amo...

British Library Electronic Table of Contents (United Kingdom)

A nonlinear free boundary-value problem of supercavitating flow past n + 1 hydrofoils is analyzed. To describe the cavities' closure mechanism, the Tulin-Terentev single-spiral-vortex model is employed. The flow domain is considered as the image of an (n + 1)-connected circular domain. The conformal map is constructed in terms of the solutions to two Riemann-Hilbert problems of the theory of symmetric automorphic functions. One of the problems is homogeneous and its coefficients are continuous functions while the second problem is inhomogeneous and has discontinuous coefficients. The exact solutions to the problems are found by using quasiautomorphic and quasimultiplicative analogs of the Cauchy kernel. The case of a single plate is considered in detail and the numerical results are report...

CERN Document Server

In this paper we deal with a new class of Clifford algebra valued automorphic forms on arithmetic subgroups of the Ahlfors-Vahlen group. The forms that we consider are in the kernel of the operator $D \\Delta^{k/2}$ for some even $k \\in {\\mathbb{Z}}$. They will be called $k$-holomorphic Cliffordian automorphic forms. $k$-holomorphic Cliffordian functions are well equipped with many function theoretical tools. Furthermore, the real component functions have also the property that they are solutions to the homogeneous and inhomogeneous Weinstein equation. This function class includes the set of $k$-hypermonogenic functions as a special subset. While we have not been able so far to propose a construction for non-vanishing $k$-hypermonogenic cusp forms for $k \

Energy Technology Data Exchange (ETDEWEB)

This paper uses a choice experiment to evaluate the consumers' willingness to pay for energy-saving measures in Switzerland's residential buildings. These measures include air renewal (ventilation) systems and insulation of windows and facades. Two groups of respondents consisting respectively of 163 apartment tenants and 142 house owners were asked to choose between their housing status quo and each one of the several hypothetical situations with different attributes and prices. The estimation method is based on a fixed-effects logit model. The results suggest that the benefits of the energy-saving attributes are significantly valued by the consumers. These benefits include both individual energy savings and environmental benefits as well as comfort benefits namely, thermal comfort, air quality and noise protection. (author)

British Library Electronic Table of Contents (United Kingdom)

Within the framework of the effective-mass approximation, using a variational method, we have calculated the effect of intense laser radiation on the binding energy of the shallow-donor impurities in a Ga1- x In x N y As1- y /GaAs single quantum well for different nitrogen and indium mole concentrations. Our numerical results show that the binding energy strongly depends on the laser intensity and frequency (via the laser dressing parameter) and it also depends on the nitrogen and indium concentrations. Impurity binding energy under intense laser fields can be tuned by changing the nitrogen and indium mole fraction.

Energy Technology Data Exchange (ETDEWEB)

This paper presents the history and objectives of the development of a standard method for the measurement of organic contaminants in biomass producer gases. Recently, a project with that title has started in the European 5{sup th} Framework Programme. The structure of this project with acronym 'Tar Protocol' is also described in this paper. The project is performed by 17 partners and continues earlier work initiated by IEA (International Energy Agency), DoE (Department of Energy) and EU (European Union) in 1998. The project aims to combine two draft Protocols that resulted from this earlier work. The Tar Protocol will be developed for accurate measurement of organic contaminants ('tars') over a large range of concentrations (1 mg/Nm{sup 3} to 100 g/Nm{sup 3}) and conditions (0 - 900 deg C; 0.9 - 60 bars). Besides, a particulate concentration will be determined too. Together with the ...

International Nuclear Information System (INIS)

First structural wall material (FSW) materials in inertial fusion energy (IFE) power reactors will be irradiated under typical repetition rates of 1-10 Hz, for an operation time as long as the total reactor lifetime. The main objective of the present work is to determine whether a continuous-pulsed (CP) approach can be an efficient method in modeling the pulsed activation process for operating conditions of FSW materials. The accuracy and practicability of this method was investigated both analytically and (for reaction/decay chains of two and three nuclides) by computational simulation. It was found that CP modeling is an accurate and practical method for calculating the neutron-activation of FSW materials. Its use is recommended instead of the equivalent steady-state method or the exact pulsed modeling. Moreover, the applicability of this method to components ...

International Nuclear Information System (INIS)

The determination of the oxidation state of ultra-trace elements in the environment, especially in the case of actinides, is of importance in many ways. Speciation techniques using radiation may comprise methods based on the detection of the nuclear and atomic radiations emitted in radioactive decay or methods using external sources of excitation. In the former instance, information can be obtained from the energy and intensity of radiation, but at present the partition method is still the most commonly used, although its reliability is questionable. Excitation with intense laser beams, as is currently being used for trace element analysis in photoacoustic and thermal lensing spectroscopic techniques, could conceivably be applied under suitable conditions to ultra-trace elements with a sensitivity approaching that of the radiochemical methods.

International Nuclear Information System (INIS)

An easy and simple method for gamma assay of large multi-gamma lines samples was introduced in this work. This method performs the assay using point source calibration. The correction factors for volume and self-attenuation are experimentally deduced from the spectra of different thicknesses samples utilizing the following two simple well known facts: large and small samples of the same homogenous material have identical specific activities; the self-attenuation of gamma line decreases as its energy increases. The method was successfully applied to naturally occurring radioactive material (NORM) large samples. This method does not require complicated mathematical procedures. Neither sample matrix data nor detector unit composition is needed.

Energy Technology Data Exchange (ETDEWEB)

In many parts of the United States, as well as other regions of the world, competing demands for fresh water or water suitable for desalination are outstripping sustainable supplies. In these areas, new water supplies are necessary to sustain economic development and agricultural uses, as well as support expanding populations, particularly in the Southwestern United States. Increasing the supply of water will more than likely come through desalinization of water reservoirs that are not suitable for present use. Surface-deployed seismic and electromagnetic (EM) methods have the potential for addressing these critical issues within large volumes of an aquifer at a lower cost than drilling and sampling. However, for detailed analysis of the water quality, some sampling utilizing boreholes would be required with geophysical methods being employed to extrapolate these sampled results to non-sampled regions of the aquifer. The research in this report ...

Energy Technology Data Exchange (ETDEWEB)

This thesis examines the costs and benefits of energy management in office buildings and investigates the relationships between operating costs, space lease contracts, and building value. Energy management be building owners and managers begins with monitoring and analysing building energy, use and continues by reducing energy consumption through operating procedure changes, equipment replacement and control personnel training and continued monitoring. The cost to complete energy management projects in 12 British Columbia office buildings is analyzed. The average before-tax internal rate of return for the 12 energy management programs was 22.1% on total expenditures of Canadian $1.2 million. Nine of the buildings are owned and occupied by the provincial government, and the return on investment directly benefits the public. However, in the three prvately owned ...

International Nuclear Information System (INIS)

The neutral Higgs boson is expected to have a mass in the region 90 endash 150thinspGeV /c"2 in various schemes within the minimal supersymmetric extension of the standard model. A first generation muon collider is uniquely suited to investigate the mass, width, and decay modes of the Higgs boson, since the coupling of the Higgs boson to muons is expected to be strong enough for it to be produced in the s channel mode in the muon collider. Because of the narrow width of the Higgs boson, it is necessary to measure and control the energy of the individual muon bunches to a precision of a few parts in a million. We investigate the feasibility of determining the energy scale of a muon collider ring with circulating muon beams of 50thinspGeV energy by measuring the turn by turn variation of the energy deposited by electrons produced by the decay of the muons. This variation is caused by the existence of an ...

International Nuclear Information System (INIS)

The purpose of this research is to investigate the micro-mechanism of deformation behavior of metallic glasses. We report the results of direct observations of short-range and medium-range structural change during tensile deformation of metallic glasses by high energy X-ray diffraction method. Cu50Zr50 and Ni30Zr70 metallic glass samples in the ribbon shape (1.5 mm width and 25 ?m) were made by using rapid quenching method. Tensile deformation added to the sample was made by using special equipment adopted for measuring the high energy X-ray diffraction. The peaks in pair distribution function g(r) for Cu50Zr50 and N30iZr70 metallic glasses move zigzag into front and into rear during tensile deformation. These results of direct observation on atomic distribution change for Cu50Zr50 and Ni30Zr70 metallic glass ribbons during tensile deformation suggest that the micro-relaxations occur.

International Nuclear Information System (INIS)

In radiotherapy treatment planning, convolution/superposition algorithms currently represent the best practical approach for accurate photon dose calculation in heterogeneous tissues. In this work, the implementation, accuracy and performance of the FFT convolution (FFTC) and multigrid superposition (MGS) algorithms are presented. The FFTC and MGS models use the same 'TERMA' calculation and are commissioned using the same parameters. Both models use the same spectra, incorporate the same off-axis softening and base incident lateral fluence on the same measurements. In addition, corrections are explicitly applied to the polyenergetic and parallel kernel approximations, and electron contamination is modelled. Spectra generated by Monte Carlo (MC) modelling of treatment heads are used. Calculations using the MC spectra were in excellent agreement with measurements for many linear accelerator types. To speed up the calculations, a number of calculation techniques were ...

Energy Technology Data Exchange (ETDEWEB)

This report is the 1992 annual progress report for the Energy Conversion and Storage Program, a part of the Energy and Environment Division of the Lawrence Berkeley Laboratory. Work described falls into three broad areas: electrochemistry; chemical applications; and materials applications. The Energy Conversion and Storage Program applies principles of chemistry and materials science to solve problems in several areas: (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes and chemical species, and (5) study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and ...

Energy Technology Data Exchange (ETDEWEB)

The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes, and (5) application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Topics include identification of new electrochemical couples for advanced rechargeable batteries, improvements in battery and fuel-cell ...

International Nuclear Information System (INIS)

The detailed electronic energy band structure of hexagonal close-packed #alpha#-zirconium, corresponding to the atomic configuration of 4d"25s"2 of its four outermost valence electrons, has been computed by the composite-wave variational version of the augmented-plane-wave(APW) method in conjunction with the X#alpha#(#alpha# = 0.70424) exchange approximation for obtaining the potentials. From these data the electronic density of states and its angular-momentum-decomposed components have been obtained by the Raubenheimer-Gilat method. These quantities are required in order to calculate the electron-phonon interaction parameter (lambda) and the superconducting transition temperature (Tsub(c)) within the framework of the theories of Gaspari and Gyorffy and McMillan. A study of the variation of Tsub(c) with the Coulomb pseudopotential (#mu#*) revealed that #mu#* = 0.1 yields the best agreement between theory and experiment for ...

Science.gov (United States)

A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the ...

Energy Technology Data Exchange (ETDEWEB)

A brief overview is given of the geological characteristics of each region of the state as they relate to potential geothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermal resources are outlined. (MHR)

International Nuclear Information System (INIS)

We have measured the neutron capture and fission cross section of "2"3"3U at the neutron time-of-flight facility n-TOF at CERN in the energy range from 1 eV to 1 MeV with high accuracy by using a high performance 4#pi# BaF_2 Total Absorption Calorimeter (TAC) as a detection device. The method, based on the shape analysis of the TAC energy response, allowing to disentangle between #gamma#'s originating from fission and capture will be presented as well as the first very preliminary results. (authors)

International Nuclear Information System (INIS)

Using the slow electrons spectrometer one can get information on the surface structure, its element composition, chemical bonds, adsorption phenomena, electron state density and surface oscillation. We have developed the methods and created the apparatus that makes it possible to investigate the electron backscattering by solid surface. We have studied the electron scattering by the polycrystalline and monocrystalline. GaAs surface in the energy range of 0 to 9 eV. The FWHM of electron energy distribution function was 70 meV. (author).

Energy Technology Data Exchange (ETDEWEB)

In order to obtain the resonance parameters in a single energy range and the corresponding covariance matrix, a reevaluation of 239Pu was performed with the code SAMMY. The most recent experimental data were analyzed or reanalyzed in the energy range thermal to 2.5 keV. The normalization of the fission cross section data was reconsidered by taking into account the most recent measurements of Weston et al. and Wagemans et al. A full resonance parameter covariance matrix was generated. The method used to obtain realistic uncertainties on the average cross section calculated by SAMMY or other processing codes was examined.

British Library Electronic Table of Contents (United Kingdom)

Abstract This article summarizes the results of a Nutrient Biomarker Study in the Women's Health Initiative, and its application to studies of the association between energy and protein consumption and the risk of major cancers and cardiovascular diseases. The presentation emphasizes measurement error modeling and related data analysis methods, since addressing measurement issues appears to be central to these topics and to progress in nutritional epidemiology more generally. The manner in which body mass index is modeled in disease association analysis is particularly challenging, since it could serve as a mediator or as a confounder of the association, and at the same time contributes valuably to energy and protein consumption assessment. A hazard ratio parameter estimation procedure tha...

Energy Technology Data Exchange (ETDEWEB)

This article deals with the need for control strategies and control systems in buildings with hybrid ventilation. In this respect, control strategies are methods of keeping certain parameters like temperature, air quality etc within specified limits. A control system is automatic and includes sensors, motors, dampers etc. The article also discusses consequences with respect to thermal comfort, air quality and energy use following selection of control parameters for controlling air masses.

Energy Technology Data Exchange (ETDEWEB)

A brief overview is given of the geological characteristics of each region of the state as they relate to potential geothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermal resources are outlined. (MHR)

Energy Technology Data Exchange (ETDEWEB)

Technology developments in semiconductor fabrication along with a rapid expansion of the market for portable devices, such as PDAs and mobile phones, make the energy consumption of embedded systems a major problem. Indeed the need to provide an increasing number of computational intensive applications and at the same time to maximize the battery life of portable devices can be seen as incompatible trends. System simulation is a flexible and convenient method for analyzinging and exploring the performance of a system or sub-system. At the same time, the increasing use of computational intensive applications strengthens the need to maximize the battery life of portable devices. As a consequence, the simulation of embedded systems for energy consumption estimation is becoming essential in order to study and explore the influence of system design choices on the system energy consumption. The original ...

Energy Technology Data Exchange (ETDEWEB)

The suitability of the sunflower for biodiesel production was discussed in terms of the reference values on carbon dioxide equivalents (CO{sub 2eq}) emissions for every phase of the biofuels chain as indicated in the European Union (EU) Directive on renewable energies. A life cycle analysis performed on the agricultural phase of the sunflower showed that CO{sub 2eq} emissions from the cultivation phase exceeded the EU reference value. This paper highlighted the relevance of allocation methods to spread out energy consumption and CO{sub 2eq} emissions among sunflower biodiesel and oilcake. Allocation was made according to the principles of mass content, energy content and the economic value of co-products. The CO{sub 2eq} reductions obtained with the 3 methods were approximately 60, 50 and 25 per cent, respectively when compared to a case without allocation. Since these ...

Energy Technology Data Exchange (ETDEWEB)

One third of the microstructure of glassy carbon (GC) consists of closed pores. Density measurements indicate that the total pore volume depends only on the heat treatment temperature and not on the heat treatment time, a characteristic of coarsening. The kinetics of coarsening of these pores on heat treatment has been investigated by analyzing the changes in specific surface area of the pores as determined by the small angle X-ray scattering (SAXS) technique. A part of the surface area change is due to thermal expansion induced microcracking. Both the superposition method after correcting the thermal expansion induced surface area change and the curve fitting method give an activation energy of 64 +/- 10 kcal/mole. This value is compared with the activation energies of various rate processes in graphite. A model of coarsening of the pores based on a vacancy migration mechanism is proposed.

Science.gov (United States)

Collective methods of ion acceleration using intense relativistic electron beams (IREB) have stimulated a great deal of interest in the past few years. The main virtue of an IREB collective ion accelerator is the high internal electric field strength. The primary drawback has been an insufficient ion energy gain or inadequate scaleability. An extensive study for generating a high quality electron beam has been done and is presented in Section 2. In Section 3 an intense ion injector study was conducted by the method of computer simulation. The last addition to the proposal was a design for producing a toroidal magnetic field. This field will be needed in a future study of high energy and high current electron beams.

International Nuclear Information System (INIS)

The local environment of Ca dopants in barium titanate, BaTiO_3, is investigated by Ca K-edge X-ray absorption near-edge structure (XANES) spectroscopy. In conjunction with experiments, first-principles calculations by two methods are systematically made. The projector-augmented wave (PAW) method is used to optimize the local structure and obtain the formation energy. The augmented plane wave plus local orbitals method is adopted to obtain theoretical XANES spectra. A comparison between experimental and theoretical XANES spectra shows that Ca dopants are located at the Ba"2"+ sites forming Ca"2"+. Formation energy calculations of Ca doped BaTiO_3 by the PAW method also give the same results. The Ca atom in BaTiO_3 is off-centering in comparison with the Ba site in BaTiO_3. The off-centering of Ca atom is newly revealed by the combination of XANES spectroscopy ...

Energy Technology Data Exchange (ETDEWEB)

The need for a hydrogen economy is driven by increasing fuel prices, depleting oil reserves and uncertainty over supplies, and concerns about global warming and environmental pollution. Alternative methods to portable energy sources such as fossil fuels are being developed that are more efficient and carbon-emission-neutral. A prospective method is to produce hydrogen as an energy carrier. This paper presented a study on the degradation of materials under conditions of the sulphur-iodine (SI) thermochemical cycle. The paper provided background information on the study and presented a schematic of the SI cycle. A literature review was presented along with materials selected, such as refractory metals, reactive metals, superalloys, glassy metals, ceramics, cermets, polymers, composites, and coatings. The experimental method was then described. A capsule method was ...

Energy Technology Data Exchange (ETDEWEB)

Health physicists from the Brookhaven National Laboratory (BNL) visited the Savannah River Site (SRS) as one of 12 facilities operated by the Department of Energy (DOE) contractors with annual collective dose equivalents greater than 100 person-rem (100 person-cSv). Their charter was to review, evaluate and summarize as low as reasonably achievable (ALARA) techniques, methods and practices as implemented. This presentation gives an overview of the two selected ALARA practices implemented at the SRS: Administrative Exposure Limits and Goal Setting. These dose control methods are used to assure that individual and collective occupational doses are ALARA and within regulatory limits.

Energy Technology Data Exchange (ETDEWEB)

This review of methods and designs of transducers for nondestructive determination of the magnitude and nature of the anisotropy of magnetic properties (permeability, induction, coercive force, energy loss due to magnetization reversal) in local portions of ferromagnetic sheet and, in some cases, in individual parts of products. The need to measure the anisotropy is considered for two angles: for the case when the anisotropy is due to the crystallographic texture and determines the main operating characteristics of widely used sheet such as electrical steel and automobile body sheet, and for crystallographically isotropic materials, in which the anisotropy of magnetic properties as a result of mechanical stresses is a measure for determining the internal stresses.

International Nuclear Information System (INIS)

The crystal field splitting of the "3H_4 ground state of the Pr ion in PrFeO_3 and PrGaO_3 has been investigated by inelastic scattering of the thermal neutrons. At several temperatures the transitions have been measured by TAS and TOF methods for polycrystalline PrFeO_3 and by the TOF method for polycrystalline PrGaO_3. Energy level schemes which are different for these materials are given. (author).

International Nuclear Information System (INIS)

The electronic structure and optical properties in tetragonal ceramics PbTiO_3, are studied by using full-potential linearized augmented plane wave method in density functional theory with the generalized gradient approximation by WIEN2K package. The theoretical calculated optical properties and energy loss spectrum yield a static refractive index of 2.59 and a plasmon energy of 22.7eV for the tetragonal phase. The effective electron number at low energy saturates near 22-23eV with the value of 50 for the effective electron number. The results show a indirect band gap of 2.2eV at the I' point in the Brillouin zone. The :calculated band structure and density of states of PbTiO_3 agree with previous experimental and theoretical results.

International Nuclear Information System (INIS)

High temperature deformation behaviour of an experimental Beta-titanium alloy Ti-10V has been studied in the temperature range 800 to 945 degree C by using the method of crosshead speed cycling. Although subgrain formation was observed but the alloy did not exhibit superplastic behaviour in the entire temperature range studied. A very large initial grain size and elongation of grains during the deformation are considered the main factors responsible for absence of superplastic behaviour. The activation energy values for regions II and III of the ln sigma vs. ln small epsilon plots are close to the lower of the two activation energy values proposed together to describe self diffusion in beta-phase suggesting that the rate controlling mechanism is that for lattice diffusion rather then grain boundary diffusion. (author)

International Nuclear Information System (INIS)

The research and development of a new type of high damping rubber damper for high rise buildings/structures to mitigate earthquake or wind-induced structural response is described in this paper. The static tests were carried out to investigate restoring force characteristics using scale model of high damping rubber damper. The repetitive tests and the temperature dependency tests were carried out to investigate variance of performance of energy absorption. It is confirmed that the damping force characteristics of the damper can be considered as that of linear viscous damping and the damper sufficiently dissipates energy for vibrations of mm order to that of generating 200% shear strain. The design methods, based on assuming linear viscous damping for the damper, has been developed. The designed values such as stiffness and damping coefficient of the damper agree well with the experimental results. (author)

International Nuclear Information System (INIS)

By method of transmission electron microscopy and measuring of microhardness the peculiarities of influence of radiation defect clusters on molybdenum radiation hardening along range path of protons with 30 MeV initial energy are studied. Decrease effect of hardening growth value and even its absence depending on irradiation dose in the range of 10-20 MeV proton energies in presence of high density of radiation defect dispersed clusters is revealed. It is shown experimentally that this effect is connected with accumulation of hydrogen up to not very high concentrations (not more than 5x10"-"4 at.%) at the expense of elastic and inelastic proton scattering. 5 refs.; 5 figs.

Energy Technology Data Exchange (ETDEWEB)

Cheap air conditioning from oceanic temperature differences is a possible new competitor for coal in coastal regions. Coal suppliers planning expansion in growing economies need to be aware of the possibilities and limitations of this new competitor. Ocean thermal energy conversion (OTEC) used to be uneconomic but the National Energy Laboratory of Hawaii (NELH) has developed a very economic method of utilising the temperature difference between warm ocean surface and cold deep ocean to generate energy for air conditioning. The article outlines the process and mentions demonstrations of OTEC technology to produce electricity and air conditioning at a site in Kailua-Kona, Hawaii. Indonesia and India have viable sites for OTEC installations, and NELH is working with Madras State on a project to construct a commercial OTEC plant in India. 2 photos.

Energy Technology Data Exchange (ETDEWEB)

Ab initio planewave pseudopotential method is used to study carbon diffusion and pairing in crystalline silicon. The calculation is performed with a 40 Ry planewave cutoff and 2x2x2 special k-point sampling with a supercell of 64 atoms. It is found that substitutional carbon attracts interstitial Si forming a <001> C interstitial with a large binding energy of 1.45 eV. The interstitial carbon is mobile and can migrate with a migration energy of 0.5 eV. The interstitial carbon can bind further to another substitutional carbon forming a substitutional carbon-interstitutional carbon pair with a binding energy of 1.0 eV. This model is used to understand the effect of high C concentration on the transient enhanced diffusion in Si.

Energy Technology Data Exchange (ETDEWEB)

An analysis was performed to determine the impact of various power system components and mission requirements on the size of solar-powered high altitude long endurance (HALE)-type aircraft. The HALE unmanned aerial vehicle (UAV) has good potential for use in many military and civil applications. The primary power system components considered in this study were photovoltaic (PV) modules for power generation and regenerative fuel cells for energy storage. The impact of relevant component performance on UAV size and capability were considered; including PV module efficiency and mass, power electronics efficiency, and fuel cell specific energy. Mission parameters such as time of year, flight altitude, flight latitude, and payload mass and power were also varied to determine impact on UAV size. The aircraft analysis method used determines the required aircraft wing aspect ratio, wing area, and total mass based on maximum ...

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 ...

Energy Technology Data Exchange (ETDEWEB)

Delayed-neutron (DN) energy spectra following thermal neutron induced fission of /sup 239/Pu as a function of time after fission have been measured, using the beta-neutron time-of-flight (TOF) spectrometer at the University of Lowell. Thermal/epithermal neutrons were produced on the 5.5-MV Van de Graaff accelerator using the /sup 7/Li(p,n)/sup 7/Be reaction. Time spectra over the neutron energy range of 0.01-4.0 MeV were measured for seven different time intervals after fission, each interval containing varying contributions from the six delayed neutrons groups. The DN energy spectra following induced thermal fission of /sup 239/Pu are compared to those resulting from induced thermal fission of /sup 235/U for each of the seven delay time intervals. Decomposition of the measured spectra into six-group DN spectra was accomplished employing an iterative least-squares method, incorporating a constraint ...

Energy Technology Data Exchange (ETDEWEB)

In the field of reactor and fuel cycle physics, particle transport plays and important role. Neutronic design, operation and evaluation calculations of nuclear system make use of large and powerful computer codes. However, current limitations in terms of computer resources make it necessary to introduce simplifications and approximations in order to keep calculation time and cost within reasonable limits. Two different types of methods are available in these codes. The first one is the deterministic method, which is applicable in most practical cases but requires approximations. The other method is the Monte Carlo method, which does not make these approximations but which generally requires exceedingly long running times. The main motivation of this work is to investigate the possibility of a combined use of the two methods in such a way as to retain their advantages while avoiding ...

Energy Technology Data Exchange (ETDEWEB)

It is clarified that the so-caned 'helicity conservation law' is never the conservation equation of the helicity K itself', but is merely 'the time change rate equation of K', which is passively and resultantly determined by the mutually independent volume and surface integral terms. It is shown that since the total helicity K can never be conserved in the real experimental systems, the conjecture of the total helicity invariance is not physically available to real magnetized plasmas in an exact sense. The well-known relaxation theory by Dr. J. B. Taylor is clarified to be neither the variational principle nor the energy principle, but be merely a mathematical calculation, using the variational calculus in order to find the minimum magnetic energy solution from the set of solutions having the same value of K. With the use of auto-correlations for physical quantities, it is presented that a novel ...

International Nuclear Information System (INIS)

Energy savings from the use of daylighting in commercial buildings are realized through implementation of photoelectric lighting controls that dim electric lights when sufficient daylight is available to provide adequate workplane illumination. The dimming level of electric lighting is based on the signal of a photosensor. Current simulation approaches for such systems are based on the questionable assumption that the signal of the photosensor is proportional to the task illuminance. This paper presents a method that simulates the performance of photosensor controls considering the acceptance angle, angular sensitivity, placement of the photosensor within a space, and color correction filter. The method is based on the multiplication of two fisheye images: one generated from the angular sensitivity of the photosensor and the other from a 180- or 360-degree fisheye image of the space as ''seen'' by the photosensor. The paper ...

Energy Technology Data Exchange (ETDEWEB)

The measurement of level in the liquid nitrogen vessel has been carried out by the weight conversion method using weigher or by putting directly a stick in the vessel. On a large CE tank, the pressure difference was read by manometer. These methods can not be used when the vessel does not put on the weigher or the pipe for manometer is stopped. We noticed the interaction between radiation ({gamma}-ray) and substance and applied it to determine the liquid nitrogen level. The results proved it the easy method for measurement of the level in the large CE tank. Cesium 137 ({gamma}-ray energy: 662 keV) was used as the radiation source. {gamma}-ray transmission dose was determined by GM survey meter. The liquid nitrogen level could be determined by using the change of the transmission dose with amount of liquid nitrogen. (S.Y.)

British Library Electronic Table of Contents (United Kingdom)

In recent years, increased attention has been focused on the use of lasers in different fabrication steps of solar cells, in particular laser doping to form emitter and/or selective emitter. In this method the laser energy is used to melt silicon, allowing the diffusion of dopant atoms to occur in the liquid phase. The main advantage of this method is the localised nature of the laser beam, which melts and diffuses a limited area without heating the bulk, therefore reducing the possible degradation associated with high temperature processes. At the University of New South Wales a novel laser doping method was developed, which combines the formation of the selective emitter with a self-aligned metallisation pattern. Despite achieving high efficiencies, concerns arose regarding the adhesion ...

British Library Electronic Table of Contents (United Kingdom)

Summary Solid state nuclear track detectors are used to determine the concentration of a particles in the environment. The standard method for assessing exposed detectors involves 2D image analysis. However 3D imaging has the potential to provide additional information relating to angle as well as to differentiate clustered hit sequences and possibly energy of a particles but this could be time consuming. Here we describe a new method for rapid high-resolution 3D imaging of solid state nuclear track detectors. A `LEXT' OLS3100 confocal laser scanning microscope (Olympus Corporation, Tokyo, Japan) was used in confocal mode to successfully obtain 3D image data on four CR-39 plastic detectors. Three-dimensional visualization and image analysis enabled characterization of track features. This ...

Energy Technology Data Exchange (ETDEWEB)

The electronic structure of the C15, or cubic-Laves-phase material, UAl/sub 2/ has been calculated using the linearized relativistic augmented-plane-wave method. The anomalous behavior of the electrical resistivity, specific heat, and magnetic susceptibility can be explained by the fine structure of the density of states near the Fermi energy alone, without the necessity of the introduction of drastic spin fluctuations or many-body effects.

Energy Technology Data Exchange (ETDEWEB)

The brochure reports on the construction and method of operation of heat pumps: - Efficiency and temperature difference - output figure - circuit processes - saving of primary energy - monovalent and bivalent plants - absorber, earth collectors - heat recovery. (HW) [Deutsch] Die Broschuere berichtet ueber den Aufbau und die Wirkungsweise von Waermepumpen: - Wirkungsgrad und Temperaturdifferenz - Leistungszahl - Kreisprozesse - Einsparung von Primaerenergie - monovalente und bivalente Anlagen - Absorber, Erdkollektoren - Waermerueckgewinnung. (HW)

International Nuclear Information System (INIS)

The method of inversion of the eigenvalue problem previously developped for nuclei with axial symmetry is extended to asymmetric equilibrium shapes. This new approach to the asymmetric rotator model is applied to the odd-mass Iridium isotopes. A satisfactory and coherent description of the observed energy spectra is obtained, especially for the lighter isotopes. (orig.).

International Nuclear Information System (INIS)

Using the PMR method the interaction of zirconium and hafnium tetrachlorides with tri.tet.butylphenyl ester of 1,2- naphthoquinonediazide (2)-5-sulfonic acid is studied. The formation of MCl_4xNQD complexes is established, the equilibrium constants and thermodynamic parameters of complexing reaction are determined. The presence of rapid ligand exchange, proceeding according to associative mechanism, is detected. The rate constants and activation energies of the exchange reaction are calculated.

Energy Technology Data Exchange (ETDEWEB)

The peculiarities of pulsed laser melting and evaporation of the superconducting ceramics are analyzed by means of numerical simulation. The appearance of the overheated metastable states in solid and liquid phases is shown as a result of the phase front dynamics and volume nature of laser energy release. A method of dynamic adaptation for the multifront Stefan problem is proposed.

International Nuclear Information System (INIS)

The study required by the West German Ministry of Research and Technology (RS 605) for the Committee on 'Future Nuclear Energy Policy' of the 9th German Parliament is concerned with the following main points: 1) Assessment of technical risks from the social aspect; 2) Discussion of terms and quantification of risks; 3) 'Engineering judgment' and 'questionable' methods in the Fast Breeder analysis of the Society for Reactor Safety (GRS); 4) Assessment criteria of potential damage. (HP).

Energy Technology Data Exchange (ETDEWEB)

Future linear colliders offer unique opportunities to study {gamma}{gamma}, {gamma}e interactions. Using the laser backscattering method one can obtain {gamma}{gamma}, {gamma}e colliding beams with energy and luminosity comparable to the electron-position luminosity or even higher. In this review physical principles of photon colliders are described and various problems, concerning the accelerator, laser, interaction region and luminosity are discussed. Some examples of physical processes are given. ((orig.)).

British Library Electronic Table of Contents (United Kingdom)

Phonon relaxation and internal friction in kaolin-and bentonite-filled PVC composites are studied. By varying the temperature and/or content of the ultrafine mineral filler in the PVC, one can control the contribution from phonon viscosity, damping force, and the effect of viscosity into the energy dissipation of ultrasonic oscillations in the MHz frequency interval. The dynamic character of the measurements makes it possible to differentiate between relaxation phenomena in the composites and to suggest methods for their controlled changes.

International Nuclear Information System (INIS)

A new method of particle identification of heavy ions through the measurement of the Bragg curve centroid and particle energy has been developed using a gas ionization chamber with a resistive anode layer. Z-resolutions comparable to the conventional #DELTA#E-E counter telescope could be rather easily attained. (orig.).

International Nuclear Information System (INIS)

Projectilelike fragments following the 80 MeV "1"6O+"2"7Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

Energy Technology Data Exchange (ETDEWEB)

An increase in the stability and reliability of a combined power system (OES) is achieved through using a control panel (PA) and regulation systems. A substantial part of the works published in this collection of works is used in the combined power systems of the Urals, the Northwest and Central Asia.

Energy Technology Data Exchange (ETDEWEB)

One of the effective methods of deep modification of the surface of steels and alloys is the combination of ion implantation and plasma nitriding. In this work, the long-range effect is demonstrated in the case of combination of the effect of high- and low-energy ions of nitrogen on a martensitic steel for each ion implantation is usually not effective, and a titanium alloy used widely in industry.

International Nuclear Information System (INIS)

The proposed method to analyze the composition of the cost of electricity is based on the energy conversion processes and the destruction of the exergy through the several thermodynamic processes that comprise a combined cycle power plant. The method uses thermoeconomics to evaluate and allocate the cost of exergy throughout the processes, considering costs related to inputs and investment in equipment. Although the concept may be applied to any combined cycle or cogeneration plant, this work develops only the mathematical modeling for three-pressure heat recovery steam generator (HRSG) configurations and total condensation of the produced steam. It is possible to study any nx1 plant configuration (n sets of gas turbine and HRSGs associated to one steam turbine generator and condenser) with the developed model, assuming that every train operates identically and in steady state. The presented model was conceived from a ...

International Nuclear Information System (INIS)

The effects of extended source-to-surface distance (SSD) on the electron beam dose profiles were evaluated for various electron beam energies - 6, 9, 12, 15 and 20 MeV - and the accuracy of various output correction methods was analysed on a Mitsubishi linear accelerator using a radiation field analyser (RFA). The dose fall-off region of the central axis depth-dose curves was nearly independent for SSDs up to 120 cm where as in the build-up region, a marginal reduction of surface dose was observed, particularly for lower energies and for smaller field sizes. Effective SSDs and virtual source distances were evaluated for field sizes ranging from 5x5 to 15x15 cm"2 for various energies. Curve fitting was done with the measured outputs with various equations and coefficients were evaluated. The accuracy of the derived output correction factors by effective SSD, virtual source distance and curve-fit ...

International Nuclear Information System (INIS)

Host matrices for actinide immobilisation will undergo the formation of large helium quantities due to alpha decay. Helium diffusion rate has to be known in order to predict the long-term behaviour of the material, and particularly, the influence of helium accumulation on mechanical properties. A nuclear reaction analysis method, namely the "3He(d, p)"4He reaction, has been used to analyse the evolution of "3He profiles after ion implantations at 1 and 3 MeV in two materials, monoclinic ZrO_2 (as a test material) and Ca_9Nd(PO_4)_5(SiO_4)F_1_._5(OH)_0_._5 britholite (envisaged for Am and Pu long-term storage). Two data processing methods are used: the classical excitation curve (proton yields versus deuteron energy) and second, the proton energy spectrum for a given deuteron energy. The characteristics of the "3He profiles (depth, width) obtained by both methods ...

International Nuclear Information System (INIS)

A computerised curve-fitting method was developed to calculate the trapping parameters in LiF TLD-100 and LiF:Mg, Ti. After irradiation in a "6"0Co field and with X rays emitted at different voltages the TL process is best described by first-order kinetics. A dependence of the trapping parameters on both the concentration of Mg and Ti and photon energy was detected. (author).

Energy Technology Data Exchange (ETDEWEB)

In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning ...

Energy Technology Data Exchange (ETDEWEB)

We present a formulation of ab initio electronic structure calculations in a finite magnetic field, which retains the simplicity and efficiency of techniques widely used in first principles molecular dynamics simulations, based on plane-wave basis sets and Fourier transforms. In addition we discuss results obtained with this method for the energy spectrum of interacting electrons in quantum wells, and for the electronic properties of dense fluid deuterium in a uniform magnetic field.

Energy Technology Data Exchange (ETDEWEB)

Two measurement methods to determine the rate of neutral free radical production by the photo-deionization of negative ion beams (PDINIB) are introduced. These methods, namely, photoelectron-current measurement by low-frequency electro-modulation probe (PMMP) and measurement of decrease in the negative-ion beam current (DNIC) were employed to evaluate the production rate in a trial surface-processing apparatus developed in the author's laboratory utilizing a steady-flux refined beam of neutral free radicals (RBNR) produced by the PDINIB procedure. A {sup 63}Cu{sup -} negative ion beam of kinetic energy E{sub i} varied up to 15 keV was irradiated with a 514.5 nm visible light beam from a 25 W CW Ar{sup +} ion laser. The detection limit of the production rate by the PMMP setup was as high as 6 x 10{sup 9} s{sup -1} under the condition that E{sub i}=15 keV, the negative-ion beam current I{sub i}=4 {mu}A and the laser ...