959 resultados para Mathematica Package


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Within the ever-changing arenas of architectural design and education, the core element of architectural education remains: that of the design process. The consideration of how to design in addition to what to design presents architectural educators with that most constant and demanding challenge of how do we best teach the design process?

This challenge is arguably most acute at a student's early stages of their architectural education. In their first years in architecture, students will commonly concentrate on the end product rather than the process. This is, in many ways, understandable. A great deal of time, money and effort go into their final presentations. They believe that it is what is on the wall that is going to be assessed. Armed with new computer skills, they want to produce eye-catching graphics that are often no more than a celebration of a CAD package. In an era of increasing speed, immediacy of information and powerful advertising it is unsurprising that students want to race quickly to presenting an end-product.

Recognising that trend, new teaching methods and models were introduced into the second year undergraduate studio over the past two years at Queen's University Belfast, aimed at promoting student self-reflection and making the design process more relevant to the students. This paper will first generate a critical discussion on the difficulties associated with the design process before outlining some of the methods employed to help promote the following; an understanding of concept, personalisation of the design process for the individual student; adding realism and value to the design process and finally, getting he students to play to their strengths in illustrating their design process like an element of product. Frameworks, examples, outcomes and student feedback will all be presented to help illustrate the effectiveness of the new strategies employed in making the design process firstly, more relevant and therefore secondly, of greater value, to the architecture student.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Context. Considerable demand exists for electron excitation data for Ni ii, since lines from this abundant ion are observed in a wide variety of laboratory and astrophysical spectra. The accurate theoretical determination of these data can present a significant challenge however, due to complications arising from the presence of an open 3d-shell in the description of the target ion. Aims. In this work we present collision strengths and Maxwellian averaged effective collision strengths for the electron-impact ex- citation of Ni ii. Attention is concentrated on the 153 forbidden fine-structure transitions between the energetically lowest 18 levels of Ni ii. Effective collision strengths have been evaluated at 27 individual electron temperatures ranging from 30–100 000 K. To our knowledge this is the most extensive theoretical collisional study carried out on this ion to date.Methods. The parallel R-matrix package RMATRX II has recently been extended to allow for the inclusion of relativistic effects. This suite of codes has been utilised in the present work in conjunction with PSTGF to evaluate collision strengths and effective collision strengths for all of the low-lying forbidden fine-structure transitions. The following basis configurations were included in the target model – 3d9 , 3d8 4s, 3d8 4p, 3d7 4s2 and 3d7 4s4p – giving rise to a sophisticated 295 j j-level, 1930 coupled channel scattering problem. Results. Comprehensive comparisons are made between the present collisional data and those obtained from earlier theoretical evaluations. While the effective collision strengths agree well for some transitions, significant discrepancies exist for others.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The main result of the note is a characterization of 1-amenability of Banach algebras of approximable operators for a class of Banach spaces with 1-unconditional bases in terms of a new basis property. It is also shown that amenability and symmetric amenability are equivalent concepts for Banach algebras of approximable operators, and that a type of Banach space that was long suspected to lack property A has in fact the property. Some further ideas on the problem of whether or not amenability (in this setting) implies property A are discussed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We present a FORTRAN 77 code for evaluation of resonance pole positions and residues of a numerical scattering matrix element in the complex energy (CE) as well as in the complex angular momentum (CAM) planes. Analytical continuation of the S-matrix element is performed by constructing a type-II Pade approximant from given physical values (Bessis et al. (1994) [421: Vrinceanu et al. (2000) [24]; Sokolovski and Msezane (2004) [23]). The algorithm involves iterative 'preconditioning' of the numerical data by extracting its rapidly oscillating potential phase component. The code has the capability of adding non-analytical noise to the numerical data in order to select 'true' physical poles, investigate their stability and evaluate the accuracy of the reconstruction. It has an option of employing multiple-precision (MPFUN) package (Bailey (1993) [451) developed by D.H. Bailey wherever double precision calculations fail due to a large number of input partial waves (energies) involved. The code has been successfully tested on several models, as well as the F + H-2 -> HE + H, F + HD : HE + D, Cl + HCI CIH + Cl and H + D-2 -> HD + D reactions. Some detailed examples are given in the text.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, we present collision strengths and Maxwellian averaged effective collision strengths for the electron-impact excitation of Ni II. Attention is expressly concentrated on the optically allowed fine-structure transitions between the 3d 9, 3d 84s, and 3d 74s 2 even parity levels and the 3d 84p and 3d 74s 4p odd parity levels. The parallel RMATRXII R-matrix package has been recently extended to allow for the inclusion of relativistic fine-structure effects. This suite of codes has been utilized in conjunction with the parallel PSTGF and PSTGICF programs in order to compute converged total collision strengths for the allowed transitions with which this study is concerned. All 113 LS terms identified with the 3d 9, 3d 84s, 3d 74s 2, 3d 84p, and 3d 74s 4p basis configurations were included in the target wavefunction representation, giving rise to a sophisticated 295 jj-level, 1930 coupled channel scattering complex. Maxwellian averaged effective collision strengths have been computed at 30 individual electron temperatures ranging from 30 to 1,000,000 K. This range comfortably encompasses all temperatures significant to astrophysical and plasma applications. The convergence of the collision strengths is exhaustively investigated and comparisons are made with previous theoretical works, where significant discrepancies exist for the majority of transitions. We conclude that intrinsic in achieving converged collision strengths and thus effective collision strengths for the allowed transitions is the combined inclusion of contributions from the (N + 1) partial waves extending to a total angular momentum value of L = 50 and further contributions from even higher partial waves accomplished by employing a "top-up" procedure.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A robust method for fitting to the results of gel electrophoresis assays of damage to plasmid DNA caused by radiation is presented. This method makes use of nonlinear regression to fit analytically derived dose response curves to observations of the supercoiled, open circular and linear plasmid forms simultaneously, allowing for more accurate results than fitting to individual forms. Comparisons with a commonly used analysis method show that while there is a relatively small benefit between the methods for data sets with small errors, the parameters generated by this method remain much more closely distributed around the true value in the face of increasing measurement uncertainties. This allows for parameters to be specified with greater confidence, reflected in a reduction of errors on fitted parameters. On test data sets, fitted uncertainties were reduced by 30%, similar to the improvement that would be offered by moving from triplicate to fivefold repeats (assuming standard errors). This method has been implemented in a popular spreadsheet package and made available online to improve its accessibility. (C) 2011 by Radiation Research Society

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Different economic valuation methodologies can be used to value the non-market benefits of an agri-environmental scheme. In particular, the non-market value can be examined by assessing the public's willingness to pay for the policy outputs as a whole or by modelling the preferences of society for the component attributes of the rural landscape that result from the implementation of the policy. In this article we examine whether the welfare values estimated for an agri-environmental policy are significantly different between an holistic valuation methodology (using contingent valuation) and an attribute-based valuation methodology (choice experiment). It is argued that the valuation methodology chosen should be based on whether or not the overall objective is the valuation of the agri-environment policy package in its entirety or the valuation of each of the policy's distinct environmental outputs.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The quick, easy way to master all the statistics you'll ever need The bad news first: if you want a psychology degree you'll need to know statistics. Now for the good news: Psychology Statistics For Dummies. Featuring jargon-free explanations, step-by-step instructions and dozens of real-life examples, Psychology Statistics For Dummies makes the knotty world of statistics a lot less baffling. Rather than padding the text with concepts and procedures irrelevant to the task, the authors focus only on the statistics psychology students need to know. As an alternative to typical, lead-heavy statistics texts or supplements to assigned course reading, this is one book psychology students won't want to be without. Ease into statistics – start out with an introduction to how statistics are used by psychologists, including the types of variables they use and how they measure them Get your feet wet – quickly learn the basics of descriptive statistics, such as central tendency and measures of dispersion, along with common ways of graphically depicting information Meet your new best friend – learn the ins and outs of SPSS, the most popular statistics software package among psychology students, including how to input, manipulate and analyse data Analyse this – get up to speed on statistical analysis core concepts, such as probability and inference, hypothesis testing, distributions, Z-scores and effect sizes Correlate that – get the lowdown on common procedures for defining relationships between variables, including linear regressions, associations between categorical data and more Analyse by inference – master key methods in inferential statistics, including techniques for analysing independent groups designs and repeated-measures research designs Open the book and find: Ways to describe statistical data How to use SPSS statistical software Probability theory and statistical inference Descriptive statistics basics How to test hypotheses Correlations and other relationships between variables Core concepts in statistical analysis for psychology Analysing research designs Learn to: Use SPSS to analyse data Master statistical methods and procedures using psychology-based explanations and examples Create better reports Identify key concepts and pass your course

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The unsteady gas dynamic phenomena in engine intake systems of the type found in racecars have been examined. In particular, the resonant tuning effects, including cylinder-to-cylinder power variations, which can occur as a result of the interaction between an engine and its airbox have been considered. Frequency analysis of the output from a Virtual 4-Stroke 1D engine simulation was used to characterise the forcing function applied by an engine to an airbox. A separate computational frequency sweeping technique, which employed the CFD package FLUENT, was used to determine the natural frequencies of virtual airboxes in isolation from an engine. Using this technique, an airbox with a natural frequency at 75 Hz was designed for a Yamaha R6 4-cylinder motorcycle engine. The existence of an airbox natural frequency at 75 Hz was subsequently confirmed by an experimental frequency sweeping technique carried out on the engine test bed. A coupled 1D/3D analysis which employed the engine simulation package Virtual 4-Stroke and the CFD package FLUENT, was used to model the combined engine and airbox system. The coupled 1D/3D analysis predicted a 75 Hz resonance of the airbox at an engine speed of 9000 rpm. This frequency was the induction frequency for a single cylinder. An airbox was fabricated and tested on the engine. Static pressure was recorded at a grid of points in the airbox as the engine was swept through a speed range of 3000 to 10000 rpm. The measured engine speed corresponding to resonance in the airbox agreed well with the predicted values. There was also good correlation between the amplitude and phase of the pressure traces recorded within the airbox and the 1D/3D predictions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We report calculations for energy levels, radiative rates and electron impact excitation rates for transitions in He-like Li II, Be III, B IV and C V. grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates. For determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) is used. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 49 levels of each ion. Collision strengths have been averaged over a Maxwellian velocity distribution and the effective collision strengths so obtained are reported over a wide temperature range up to 10(6) K. Comparisons have been made with similar data obtained from the flexible atomic code (FAC) to highlight the importance of resonances, included in calculations from darc, in the determination of effective collision strengths. Discrepancies between the collision strengths from darc and fac, particularly for weak transitions and at low energies, have also been discussed. Additionally, lifetimes are also listed for all calculated levels of the above four ions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, we report calculations of energy levels, radiative rates and electron impact excitation rates for transitions in Li-like Si XII, He-like Si XIII and H-like Si XIV. The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) is used. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 24 levels of Si XII, 49 levels of Si XIII and 25 levels of Si XIV, belonging to the n≤5 configurations. Collision strengths have been averaged over a Maxwellian electron velocity distribution and the effective collision strengths so obtained are reported over a wide temperature range below 107 K. Comparisons have been made with similar data obtained from the flexible atomic code (fac) to highlight the importance of resonances, included in calculations from darc, in the determination of effective collision strengths. Discrepancies between the collision strengths from darc and fac, particularly for weak transitions and at low energies, are also discussed. Additionally, lifetimes are listed for all calculated levels of the above three ions, although no measurements are available with which to compare.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We report calculations of energy levels, radiative rates and electron impact excitation rates for transitions in H-like N VII, O VIII, F IX, Ne X and Na XI. The general-purpose relativistic atomic structure package (grasp) is adopted for calculating energy levels and radiative rates, while the Dirac atomic R-matrix code (DARC) and the flexible atomic code (FAC) are used for determining the collision strengths and subsequently the excitation rates. Oscillator strengths, radiative rates and line strengths are listed for all E1, E2, M1 and M2 transitions among the lowest 25 levels of the above five ions. Collision strengths have been averaged over a Maxwellian velocity distribution, and the effective collision strengths so obtained are reported over a wide temperature range below 10(7) K. Additionally, lifetimes are also given for all the calculated energy levels of the above five ions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, we report calculations of energy levels, radiative rates and electron impact excitation rates for transitions in Li-like N V, F VII, Ne VIII and Na IX. The general-purpose relativistic atomic structure package (GRASP) is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code (DARC) and the flexible atomic code (FAC) are used. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 24 levels of N V, F VII, Ne VIII and Na IX. Collision strengths have been averaged over a Maxwellian velocity distribution and the effective collision strengths so obtained are reported over a wide temperature range below 10(6.6) K. Additionally, lifetimes are also reported for all calculated levels of the above four ions.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Aims. In this paper we report on calculations of energy levels, radiative rates, oscillator strengths, line strengths, and effective collision strengths for transitions among the lowest 362 levels of the (1s22s22p6) 3s23p5, 3s3p6, 3s23p43d, 3s3p53d, 3s23p33d2, 3s3p43d2, 3p63d, and 3s23p44 configurations of Cr viii. Methods. The general-purpose relativistic atomic structure package (grasp) and flexible atomic code (fac) are adopted for the calculations. Results. Radiative rates, oscillator strengths, and line strengths are reported for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), and magnetic quadrupole (M2) transitions among the 362 levels. Comparisons are made with earlier available results and the accuracy of the data is assessed. Additionally, lifetimes for all 362 levels are listed, although comparisons with other theoretical results are limited to only a few levels. Our energy levels are estimated to be accurate to better than 3% (within 0.4 Ryd), whereas results for other parameters are probably accurate to better than 20%. Finally, electron impact collision strengths and excitation rates are computed for all transitions over a wide energy (temperature) range. For these calculations, FAC is adopted and results in the form of effective collision strengths are reported over a wide temperature range of 105.0−106.6 K.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We report calculations of energy levels, radiative rates and electron impact excitation cross
sections and rates for transitions in He-like Cl XVI, K XVIII, Ca XIX and Sc XX. The grasp
(general-purpose relativistic atomic structure package) is adopted for calculating energy levels
and radiative rates. To determine the collision strengths and subsequently the excitation rates,
the Dirac atomic R-matrix code (darc) is used. Oscillator strengths, radiative rates and line
strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 49 levels of
each ion. Collision strengths are averaged over a Maxwellian velocity distribution and the
effective collision strengths obtained listed over a wide temperature range up to 107.4 K.
Comparisons are made with similar data obtained from the flexible atomic code (fac) to
highlight the importance of resonances, included in calculations with darc, in the
determination of effective collision strengths. Discrepancies between the collision strengths
from darc and fac, particularly for forbidden transitions, are also discussed. Additionally,
theoretical lifetimes are listed for all the 49 levels of the above four ions.