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The purpose of this paper is to explain the choice of Alpert multi‐wavelet as basis functions to discrete Fredholm integral equation of the second kind by using Petrov‐Galerkin method.

In this process, two kinds of matrices are obtained from inner product between basis of test space and trial space; some of them are diagonal with positive elements and some others are invertible. These matrices depend on type of selection of test and trial space basis.

In this process, solution of Fredholm integral equation of the second kind is found by solving the generated system of linear equations.

In previous work, convergence of Petrov‐Galerkin method has been discussed with some restrictions on degrees of chosen polynomial basis, but in this paper convergence is obtained for every degree. In point of computation, because of appearance of diagonal and invertible matrices, a small dimension system with a more accurate solution is obtained. The numerical examples illustrate these facts.

The purpose of this study is to explore the applications of 3D printing in space sectors. The authors have highlighted the potential research gap that can be explored in the current field of study. Three-dimensional (3D) printing is an additive manufacturing technique that uses metallic powder, ceramic or polymers to build simple/complex parts. The parts produced possess good strength, low weight and excellent mechanical properties and are cost-effective. Therefore, efforts have been made to make the adoption of 3D printing successful in space so that complex parts can be manufactured in space. This saves a considerable amount of both time and carrying cost. Thereof the challenges and opportunities that the space sector holds for additive manufacturing is worth reviewing to provide a better insight into further developments and prospects for this technology.

The potentiality of 3D printing for the manufacturing of various components under space conditions has been explained. Here, the authors have reviewed the details of manufactured parts used for zero-gravity missions, subjected to onboard international space station conditions and with those manufactured on earth. Followed by the major opportunities in 3D printing in space which include component repair, material characterization, process improvement and process development along with the new designs. The challenges like space conditions, availability of power in space, the infrastructure requirements and the quality control or testing of the items that are being built in space are explained along with their possible mitigation strategies.

These components are well comparable with those prepared on earth which enables a massive cost saving. Other than the onboard manufacturing process, numerous other components as well as a complete robot/satellite for outer space applications were manufactured by additive manufacturing. Moreover, these components can be recycled onboard to produce feedstock for the next materials. The parts produced in space are bought back and compared with those built on earth. There is a difference in their nature, i.e. the flight specimen showed a brittle nature, and the ground specimen showed a denser nature.

This review discusses the advancements of 3D printing in space and provides numerous examples of the applications of 3D printing in space and space applications. This paper is solely dedicated to 3D printing in space. It provides a breakthrough in the literature as a limited amount of literature is available on this topic. This paper aims at highlighting all the challenges that additive manufacturing faces in the space sector and also the future opportunities that await development.

Aims to present a boundary integral equation method for solving Laplace's equation Δu=0 with nonlinear boundary conditions.

The nonlinear boundary value problem is reformulated as a nonlinear boundary integral equation, with u on the boundary as the solution being sought. The integral equation is solved numerically by using the collocation method on smooth or nonsmooth boundary; the singularities of solution degrade the rates of convergence.

Variants of the methods for finding numerical solutions are suggested. So these methods have been compared with respect to number of iterations.

Numerical experiments show the efficiency of the proposed methods.

Provides new methods to solve nonlinear weakly singular integral equations and discusses difficulties that arise in particular cases.

A numerical model is presented for the computation of unsteady two‐fluid interfaces in nonlinear porous media flow. The nonlinear Forchheimer equation is included in the Navier‐Stokes equations for porous media flow. The model is based on capturing the interface on a fixed mesh domain. The zero level set of a pseudo‐concentration function, which defines the interface between the two fluids, is governed by a time‐dependent advection equation. The time‐dependent Navier‐Stokes equations and the advection equation are spatially discretized by the finite element (FE) method. The fully coupled implicit time integration scheme and the explicit forward Eulerian scheme are implemented for the advancement in time. The trapezoidal rule is applied to the fully implicit scheme, while the operator‐splitting algorithm is used for the velocity‐pressure segregation in the explicit scheme. The spatial and time discretizations are stabilized using FE stabilization techniques. Numerical examples of unsteady flow of two‐fluid interfaces in an earth dam are investigated.

Steady-state visual evoked potential (SSVEP) has been widely used in the application of electroencephalogram (EEG) based non-invasive brain computer interface (BCI) due to its characteristics of high accuracy and information transfer rate (ITR). To recognize the SSVEP components in collected EEG trials, a lot of recognition algorithms based on template matching of training trials have been proposed and applied in recent years. In this paper, a comparative survey of SSVEP recognition algorithms based on template matching of training trails has been done.

To survey and compare the recently proposed recognition algorithms for SSVEP, this paper regarded the conventional canonical correlated analysis (CCA) as the baseline, and selected individual template CCA (ITCCA), multi-set CCA (MsetCCA), task related component analysis (TRCA), latent common source extraction (LCSE) and a sum of squared correlation (SSCOR) for comparison.

For the horizontal comparative of the six surveyed recognition algorithms, this paper adopted the “Tsinghua JFPM-SSVEP” data set and compared the average recognition performance on such data set. The comparative contents including: recognition accuracy, ITR, correlated coefficient and R-square values under different time duration of the SSVEP stimulus presentation. Based on the optimal time duration of stimulus presentation, the author has also compared the efficiency of the six compared algorithms. To measure the influence of different parameters, the number of training trials, the number of electrodes and the usage of filter bank preprocessing were compared in the ablation study.

Based on the comparative results, this paper analyzed the advantages and disadvantages of the six compared SSVEP recognition algorithms by considering application scenes, real-time and computational complexity. Finally, the author gives the algorithms selection range for the recognition of real-world online SSVEP-BCI.

The authors contribute to practice-driven institutionalism by examining how the introduction of new field-level evaluation practices may facilitate encroachment of highly institutionalized organizational fields by new institutional logics. The authors conducted an inductive study of a trial of social impact bonds in the field of social integration services in Finland. Our analysis elaborates how new field-level evaluation practices created an experimental space that induced organizational practice experimentation, reconfigured relationships among field members, and lowered the barriers to entry for new organizations. The authors theorize how evaluation practices may create experimental spaces by suspending the carriers of established logics and legitimizing institutional innovations. The authors further elaborate how such spaces can bring about a parallel “shadow field” by inducing bottom-up experimentation aligned with a new institutional logic.

The purpose of this paper is to highlight the provision of therapy for witnesses who have a learning disability prior to and following a criminal trial. Authors will reflect on clinical practice whilst stressing that this area of work is in its infancy and both continue to learn through continued reflection and each new experience.

The paper broadly describes the nature of pre-trial therapy followed by reflection by a Counsellor and Supervisor on their clinical practice.

Authors describe some of the common themes that arise whilst providing pre-trial therapy.

The authors hope that the paper will encourage professionals involved in Safeguarding cases to fully consider the emotional needs of victims and to seek timely therapeutic support where the need presents. They also hope that it will encourage practitioners from various professions to consider providing this specialist and delicate type of therapy whilst highlighting the need for good supervision.

There is a paucity of written information about this specific subject area. Although safeguarding of vulnerable adults has grown considerably over the last decade and investigations are now more likely to lead to legal action, the availability of emotional support for victims who have learning disabilities needs to be addressed.

In this paper, I apply the discourse of transitional justice to the case study of survivor docents at the Japanese American National Museum, a site that has come to represent and serve as a form of reparation for the traumatic memory of Japanese American internment during World War II. As a longer term supplement to trials or Truth and Reconciliation Commissions or an alternative in cases where no such structures exist, I illustrate how the museum tour becomes an empowering platform for survivors of the American Internment camps to work through and instrumentalize traumatic memories within the dialogic museum sphere, even as this alternative space forms its own new silences. Thus, by applying the very theories and criticisms through which scholars of memory politics evaluate official platforms of transitional justice, I aim to complicate and evaluate this alternative form of testimony, and in so doing explore areas of growth in the fields of both transitional justice and museum practice. Bridging the gap between testimony, oral history, and museum interpretation, survivor docents represent a sustained dialogic approach to history that perpetuates, preserves, and activates – rather than resolves – discourse around contentious memories.