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This study aims to propose an improved affine interval truncation algorithm to restrain interval extension for interval function.

To reduce the occurrence times of related variables in interval function, the processing method of interval operation sequence is proposed.

The interval variable is evenly divided into several subintervals based on correlation analysis of interval variables. The interval function value is modified by the interval truncation method to restrain larger estimation of interval operation results.

Through several uncertain displacement response engineering examples, the effectiveness and applicability of the proposed algorithm are verified by comparing with interval method and optimization algorithm.

The main objective is to develop an efficient BEM scheme for the numerical solution of two‐dimensional heat problems. Our scheme will be of the re‐initialization type, in which the domain integrals are computed by a recursion relation which depends only on the boundary temperature and flux at previous time step. To obtain the re‐initialization approach, we will use in the integral representation formula a Green function corresponding to zero temperature in a box containing the original domain, instead of using the classical free space fundamental solution. This Green function is given in terms of the original fundamental solution plus a regular solution of the heat equation inside the domain under consideration. It can therefore be used in the integral representation formula of the heat equation (direct formulation) to obtain the solution of a heat problem in such a domain. The Green function mentioned can be obtained by the images method, and the resulting source series can also be rewritten in terms of a double Fourier series, that we will use in the domain integral of the integral representation formula to transform such integral into equivalent surface integrals.

Optimal switching angles are investigated for minimizing accumulated numerical errors when the dual‐Euler method is used in the simulation of angular rotation.

First, round‐off errors are theoretically modeled with a simplified mathematical representation of rotation. Round‐off errors take critical roles in the vicinity of indefinite points because they cause major numerical inaccuracy in very large numerical values represented with limited binary numbers. Optimal switching angles of (±π/4, ±3π/4) are derived and numerically examined. With a more practical and severe rotational model, the switching angles are numerically tested.

In conclusion, switching pitch angles of (±π/4, ±3π/4) yield near minimum numerical errors in angular parameters of pitch, yaw, and roll if truncation errors are not dominant by using high‐order integration algorithms and small step sizes. It is also noticed that accumulated numerical errors increase dramatically if pitch and roll angles are switched beyond the optimal angles with a little margin.

Optimal switching angles in the dual‐Euler method are identified based on the truncation error analysis. The mechanism of accumulated numerical errors in the dual‐Euler method, which depends on switching angles, is also revealed.

Solutions for the earth return mutual impedance play an important role in analyzing couplings of multi-conductor systems. Generally, the mutual impedance is approximated by Pollaczek integrals. The purpose of this paper is devising fast algorithms for calculation of this kind of improper integrals and its applications.

According to singular points, the Pollaczek integral is divided into two parts: the finite integral and the infinite integral. The finite part is computed by combining an efficient Levin method, which is implemented with a Chebyshev differential matrix. By transforming the integration path, the tail integral is calculated with help of a transformed Clenshaw–Curtis quadrature rule.

Numerical tests show that this new method is robust to high oscillation and nearly singularities. Thus, it is suitable for evaluating Pollaczek integrals. Furthermore, compared with existing method, the presented algorithm gives high-order approaches for the earth return mutual impedance between conductors over a multilayered soil with wide ranges of parameters.

An efficient truncation strategy is proposed to accelerate numerical calculation of Pollaczek integral. Compared with existing algorithms, this method is easier to be applied to computation of similar improper integrals, such as Sommerfeld integral.

Calculating the exact top event probability of fault trees is an important analysis in quantitative risk assessments. However, it is a difficult problem for the trees with complex structure. Therefore, the paper aims to provide an efficient calculation method to obtain an exact top event probability of a fault tree with many repeated events when the minimal cut sets of the tree model are given.

The method is based on the inclusion‐exclusion method. Generally, the inclusion‐exclusion method tends to get into computational difficulties for a large‐scale fault tree. The computation time has been reduced by enumerating only non‐canceling terms.

The method enables the calculation of the probability more quickly than the conventional method. The effect increases as the number of repeated events increases, namely the tree structure becomes complex. This method also can be applied to obtain the lower and upper bounds of the top event probability easily.

The paper expresses the top event probability by using only non‐canceling terms. This is the first application in fault tree analysis.

The purpose of this paper is to identify a new and simple two‐end algorithm for fault location identification and characterization, in electrical distribution systems.

The developed diagnostic algorithm is based on a simple model of the network using a lumped parameters representation.

Test results have proved the approach to be efficient, allowing a precise fault identification and location while not requiring synchronized measures from the two ends.

There is a need for measurement systems at all MV/LV substations.

Applicability with limited investments is not possible where metering systems are not so diffused, although smart grids and DG units require such infrastructures. Moreover, utilities are quite interested in such issues, since the new required quality standards put severe constraints on faults management and clearance.

The paper presents a new and easier diagnostic algorithm for faults diagnosis in distribution systems.

Presents a method of obtaining an optimal mesh in the finite element analysis of two‐dimensional linear elastodynamic problems under transient dynamic loading, which is based on a generalization of the Z‐Z criterion for discretization error estimation for time‐dependent problems. The optimal mesh limits the error due to discretization within a prescribed value, and studies of all other possible errors involved in finite element transient dynamic analysis are carried out systematically. Also proposes methods to study and limit the modal truncation error. Numerous examples show the capabilities of the proposed methods and the importance of the optimal mesh and modal truncation error in finite element transient dynamic analysis.

A number of techniques have been studied for the automatic assignment of controlled subject headings and classifications from free indexing. These techniques involve the automatic manipulation and truncation of the free‐index phrases assigned to a document and the use of a manually‐constructed thesaurus and automatically‐generated dictionaries together with statistical ranking and weighting methods. These are based on the use of a statistically‐generated ‘adhesion coefficient’ which reflects the degree of association between the free‐indexing terms, the controlled subject headings, and the classifications. By the analysis of a large sample of manually‐indexed documents the system generates dictionaries of free‐language and controlled‐language terms together with their associated classifications and adhesion coefficients. Having learnt from the manually‐indexed documents the system uses these dictionaries in the subsequent automatic classification procedure. The accuracy and cost‐effectiveness of the automatically‐assigned subject headings and classifications has been compared with that of the manual system. The results were encouraging and the costs comparable to those of a manual system.

Electrical capacitance tomography (ECT) and electrical resistance tomography (ERT) are promising techniques for multiphase flow measurement due to their high speed, low cost, non-invasive and visualization features. There are two major difficulties in image reconstruction for ECT and ERT: the “soft-field”effect, and the ill-posedness of the inverse problem, which includes two problems: under-determined problem and the solution is not stable, i.e. is very sensitive to measurement errors and noise. This paper aims to summarize and evaluate various reconstruction algorithms which have been studied and developed in the word for many years and to provide reference for further research and application.

In the past 10 years, various image reconstruction algorithms have been developed to deal with these problems, including in the field of industrial multi-phase flow measurement and biological medical diagnosis.

This paper reviews existing image reconstruction algorithms and the new algorithms proposed by the authors for electrical capacitance tomography and electrical resistance tomography in multi-phase flow measurement and biological medical diagnosis.

The authors systematically summarize and evaluate various reconstruction algorithms which have been studied and developed in the word for many years and to provide valuable reference for practical applications.

There has been a massive investment in the installation of online catalogs: in selection, in the supporting infrastructure of terminals and networks, in catalog record conversion, in training, and, lately, in linking online catalogs with other online systems. In contrast, the state‐of‐the‐art of the functionality of online library catalogs has advanced little in the past few years. Rather it has been a matter of existing systems being upgraded towards the functionality of the better systems and of refinements being added. It is time for a further advance in online catalog design. We believe that the next generation of online catalogs should and will have features such as those discussed and illustrated in this article.