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The aim of the paper is to demonstrate a fast numerical solution for Raman fiber amplifier equations using proposed guess functions and MATLAB intrinsic properties. MATLAB BVP solvers are addressed for the solution.

The guess functions proposed for the solution of RFA equations using MATLAB BVP solvers are derived from Taylor expansion of pump and signal wave near the boundary to specifically obtain convergence for the initial mesh point. The guess functions increase simulation speed significantly. In order to improve the simulation speed further, vectorization and analytical Jacobians are introduced. Comparisons among bvp4c and bvp5c have been made with respect to total pump power, number of signals, vectorization with/without analytical Jacobians, fiber length, relative tolerance and continuation method. The simulations are performed to determine the effect of the run time on the choice of the number of equally spaced mesh points (N) in the initial guess, and thus optimal N values are found.

MATLAB BVP solvers have been proven to be effective for the numerical solution of RFAs with the proposed guess functions. In particular, with vectorizing, run time reduction is between 2.1 and 5.4 times for bvp4c and between 1.6 and 2.1 times for bvp5c and in addition to vectorizing, with the introduction of the analytical Jacobians, the reduction is between 2.4 and 6.2 times for bvp4c and 1.7 and 2.2 times for bvp5c, respectively, depending on the total pump power between 1,000 mW and 2,000 mW and the number of signals. Also, simulation results show that the efficiency of the solution with proposed guess functions is improved more than six times compared with those of previously reported continuation methods. Results show that the proposed guess functions with the vectorization and analytical Jacobians can be used for the performance evaluation of RFAs for the high power systems/long gain fiber span.

The robust improvement of the solution proposed in this paper lies in the fact that the derived guess functions for the RFAs are highly effective in the sense that they assist the solver to converge to the solution for any total pump power value in a wide range from 1 to 3,000 mW and for any fiber lengths ranging 1 to 200 km which are used in practical applications. Hence, it is practicable for the performance evaluation of the existing RFA networks.

The novelty of this method is that, starting with the co‐propagating single pump and signal RFA schema, the authors derived the guess function specifically for the initial mesh points rather than using its analytical approximations. Moreover, the solution is generalized for co‐/counter propagating pumps/signals with the curve fitted coefficient(s).

Image interactivity allows the customer to create and manipulate visual images of a product on a Web site. We measured the effect of exposure to an image interactivity function from an apparel retailer’s Web site on approach responses towards the retailer. The image interactivity function from the Web site allowed participants to mix and match apparel product images to help determine how well they coordinated. Dependent variables used to tap approach responses were attitude towards the online store, willingness to purchase from the online store, willingness to return to the online store, probability of spending more time than planned shopping on the site, and likelihood of patronizing the online retailer’s bricks‐and‐mortar store. We employed a repeated‐measures experimental design with 103 subjects. Paired t‐tests provided empirical support for the effect of image interactivity on enhancing approach responses towards the retailer. However, differences in approach responses existed between males and females. Marketing implications were provided.

The purpose of this paper is to demonstrate an effective and faster numerical solution for nonlinear‐coupled differential equations describing fiber amplifiers which have no explicit solution. MATLAB boundary value problem (BVP) solver of bvp6c function is addressed for the solution.

Coding method with the bvp6c is introduced, signal evolution, threshold calculation method is introduced, gain and noise figure are plotted and superiority of the bvp6c solver is compared with the Newton‐Raphson method.

bvp6c function appears to be an effective tool for the solution fiber amplifier equations and can be used for different pump configurations of BFAs and RFAs. The excellent agreement between the proposed and reported results shows the reliability of the proposed threshold power calculation method.

The paper eases the work of the fiber optic research community, who suffer from two point BVPs. Moreover, the stiffness of the signal evolution which is faced with high pump powers and/or long fiber lengths can be solved with continuation. This superiority of the solver can be used to overcome any stiff changes of the signals for the future studies.

The main outcome of this paper is the numerically calculation of the threshold values of fiber amplifiers without the necessity of the experiment. The robustness improvement of the solution is that the solver is able to solve the equations even with the poor guess values and the solution can be obtained without the necessity of analytical Jacobian matrix.

MATLAB bvp6c solver has proven to be effective for the numerical solution of nonlinear‐coupled intensity differential equations describing fiber amplifiers with two‐point boundary values. Beside the signal evolution, thresholds of Brillouin and Raman fiber amplifiers can also be calculated by using the proposed solver. This is a notable and promising improvement of the paper, at least from a fiber optic amplifier designer point of view.

Determines whether iconic interfaces might work with online public access catalogues (OPACs), and assesses problems which students encounter in using icons. Students from the UK and France were asked to identify IBM, Mac and hand‐drawn icons and guess their functions. Mac icons were the most easy and hand‐drawn icons the least easy to identify. A number of students failed to guess the icon function second time round. Results suggest that an icon‐based OPAC interface could be popular, but would require careful design, particularly for a multilingual interface.

In this paper, various regularization methods are numerically implemented using the boundary element method (BEM) in order to solve the Cauchy steady‐state heat conduction problem in an anisotropic medium. The convergence and the stability of the numerical methods are investigated and compared. The numerical results obtained confirm that stable numerical results can be obtained by various regularization methods, but if high accuracy is required for the temperature, or if the heat flux is also required, then care must be taken when choosing the regularization method since the numerical results are substantially improved by choosing the appropriate method.

A system for solving a wide variety of inverse and optimization problems in solid mechanics is introduced. The system consists of a general purpose finite element method (FEM) analysis system “Elfen” and a shell which controls this system. The shell functions as a stand‐alone programme, so the system is physically divided into two separated parts. The “optimization part”, which corresponds to the shell, possesses optimization and inverse problem solution algorithms. The “analysis part”, which corresponds to an FEM system, serves for the definition of the objective function to which these algorithms are applied. The shell has a user interface implemented in the form of file interpreter which imposes a great flexibility at the definition of various optimization and inverse problems, including parameter identification in constitutive modelling, frictional contact problems and heat transfer. Concepts of the shell are discussed in detail.

Earlier work often referred to as the ‘hole in the wall’ experiments has shown that groups of children can leam to use public computers on their own. This paper presents the method and results of an experiment conducted to investigate whether such unsupervised group learning in shared public spaces is universal. The experiment was conducted with ‘hole in the wall’ (minimally invasive education, or MIE) kiosks in 23 locations in rural India. Focus groups in each location were tested for computer literacy for 9 months. Results, which are discussed in the paper, show that groups of children can leam to use computers and the Internet on their own, irrespective of who or where they are. The paper also discusses the engineering considerations for building such ‘hole in the wall’ computers in public spaces.

The purpose of this paper is to describe the process and implications of usability testing a prototype version of the Letters of 1916 Digital Edition.

The paper presents the testing, the lessons learned and how those lessons informed the subsequent redesign of the site.

Results imply that a majority of users, even digital humanists, were not looking for a unique and specialised interface, but assumed – and preferred – a user experience that reflects common search systems. Although the audience for digital humanities sites is becoming increasingly diverse, the needs of the different user groups may be more similar than had previously been assumed.

The usability test employed 11 participants, five of whom were coded as “general public”. Four of these five had previously volunteered to transcribe and upload letters. This meant that they were already familiar with the project and with the Letters of 1916 Transcription Desk. However, their prior involvement was a result of their genuine interest in the site, thus ensuring that their interactions during testing were more realistic.

The lesson learned may be useful for the Digital Editions of future crowdsourced humanities projects.

Letters of 1916 is the first crowdsourced humanities project in Ireland. The theme of the project is topical, emotive and socially important in Ireland and among Irish diaspora today. The project’s content has been created by the “ordinary citizens of Ireland” and they are likely to be the major users of the Digital Edition. The study explores how the Digital Edition can support these users, while also facilitating the range of traditional scholars and digital humanities researchers.

Strategic decision‐making is difficult because predicting the future in any detail is simply impossible. If we could get a handle on the relationships between decisions of the past and their effects on later business performance, though, we could probably discover which decisions were most significant to performance. This, in turn, would give us clues about the relationship between strategic decisions of the future and their effects on performance.