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The purpose of this paper is to present an analytical calculation for estimating the leakages field distribution in surface-mounted permanent magnet synchronous motors (SMPMSMs) according to a sub-domain field model for eccentricity fault detection.

The magnetic field domain is classified into four sub-domains of PMs, air gap, stator core and outer region. In the proposed method, the governing equations taking the rotor eccentricity effect into account per region and the interface boundary conditions between sub-domains are formulated using the regular perturbation technique, Taylor series and Fourier series expansion. Maxwell's equations are solved in different regions in the polar coordinate system regarding the boundary conditions.

The radial and tangential components of electromagnetic field distribution in all sub-domains of one SMPMSM are obtained using the proposed method analytically. Finite element analysis is used to validate the results of the proposed method; the results indicated that the analytical model matches the finite-element prediction up to 30% eccentricity, except for some peak values that depend on the harmonic order value. The results of this paper demonstrated that in the event of eccentricity, an asymmetric magnetic field is generated in the outer region of the machine. Although its amplitude is small, it can be an indicator for detecting eccentricity faults from the outside environment of the machine.

The formulas presented in this paper can be applied as a new technique for detecting eccentricity faults in these motors from the outside environment.

An analytical sub-domain model is developed for predicting the armature magnetic field in permanent magnet vernier machine (PMVM) which has either non-overlapping or overlapping windings. The developed model accounts for tooth-tips and flux modulation pole slots (FMPs). The paper aims to discuss these issues.

It is obtained by solving Poisson’s and Laplace’s equations in polar coordinates for each sub-domain, i.e. air gap, slots, slot openings at tooth-tips and FMP slots. Armature reaction field distributions in slots, slot openings FMPs, air-gap and magnet region and winding inductances are obtained from the analytical method and compared by finite element analysis.

It is found that the developed model can be employed to accurately predict the armature field and winding inductance for any combination of slots/FMPs/permanent magnets. In addition, it is observed that the winding inductance is high which results in significant armature reaction and poor power factor in PMVM.

The main contributions include: first, accurate sub-domain model for PMVM is proposed for armature reaction which is not addressed in literature; second, the model accounts the interaction between FMP and slot; and finally, developed sub-domain model is also used for inductance calculation.

Citation is an important measure of quality, and it plays a vital role in evaluating scientific research. However, citation advantage varies from discipline to discipline, subject to subject and topic to topic. This study aims to compare the citation advantage of open access and toll access articles from four subfields of computer science.

This research studies the articles published by two prestigious publishers: Springer and Elsevier in the author-pays charges model from 2011 to 2015. For experimentation, four sub-domains of computer science are selected including (a) artificial intelligence, (b) human–computer interaction, (c) computer vision and graphics, and (d) software engineering. The open-access and toll-based citation advantage is studied and analyzed at the micro level within the computer science domain by performing independent sample t-tests.

The results of the study highlight that open access articles have a higher citation advantage as compared to toll access articles across years and sub-domains. Further, an increase in open access articles has been observed from 2011 to 2015. The findings of the study show that the citation advantage of open access articles varies among different sub-domains of a subject. The study contributed to the body of knowledge by validating the positive movement toward open access articles in the field of computer science and its sub-domains. Further, this work added the success of the author-pays charges model in terms of citation advantage to the literature of open access.

To the best of the authors’ knowledge, this is the first study to examine the citation advantage of the author-pays charges model at a subject level (computer science) along with four sub-domains of computer science.

Due to high electromagnetic torque at low speed, vernier machines are suitable for direct-drive applications such as electric vehicles and wind power generators. The purpose of this paper is to present an exact sub-domain model for analytically predicting the open-circuit magnetic field of permanent magnet vernier machine (PMVM) including tooth tips. The entire field domain is divided into five regions, viz. magnets, air gap, slot openings, slots, and flux-modulation pole slots (FMPs). The model accounts for the influence of interaction between PMs, FMPs and slots, and radial/parallel magnetization.

Magnetic field distributions for slot and air-gap, flux linkage, back-EMF and cogging torque waveforms are obtained from the analytical method and validated by finite element analysis (FEA).

It is found that the developed sub-domain model including tooth tips is very accurate and is applicable to PMVM having any combination of slots/FMPs/PMs.

The main contributions include: accurate sub-domain model for PMVM is proposed for open-circuit including tooth-tip which cannot be accounted for in literature; the model accounts the interaction between flux modulation pole (FMP) and slot; developed sub-domain model is accurate and applicable to any slot/FMP/PM combinations; and it has investigated the influence of FMP/slot opening width/height on cogging torque.

This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell stress tensor (MST) method and sub-domain modelling for design of segmented PM(SPM) consequent pole flux switching machine (SPMCPFSM). Electric machines, especially flux switching machines (FSMs), are accurately modeled using numerical-based finite element analysis (FEA) tools; however, despite of expensive hardware setup, repeated iterative process, complex stator design and permanent magnet (PM) non-linear behavior increases computational time and complexity.

This paper reviews various alternate analytical methodologies for electromagnetic performance calculation. In above-mentioned analytical methodologies, no-load phase flux linkage is performed using LPMEC, magnetic co-energy for cogging torque, LE for magnetic flux density (MFD) components, i.e. radial and tangential and MST for instantaneous torque. Sub-domain model solves electromagnetic performance, i.e. MFD and torque behaviour.

The reviewed analytical methodologies are validated with globally accepted FEA using JMAG Commercial FEA Package v. 18.1 which shows good agreement with accuracy. In comparison of analytical methodologies, analysis reveals that sub-domain model not only get rid of multiples techniques for validation purpose but also provide better results by accounting influence of all machine parts which helps to reduce computational complexity, computational time and drive storage with overall accuracy of ∼99%. Furthermore, authors are confident to recommend sub-domain model for initial design stage of SPMCPFSM when higher accuracy and low computational cost are primal requirements.

The model is developed for high-speed brushless AC applications.

The SPMCPFSM enhances electromagnetic performance owing to segmented PMs configuration which makes it different than conventional designs. Moreover, developed analytical methodologies for SPMCPFSM reduce computational time compared with that of FEA.

This paper aims to present a review of research developments relating to the application of building information modeling (BIM) to facilities management (FM). It sheds light on major technical and organizational issues with the view of identifying how existing BIM for FM knowledge applies to large capital projects.

The study adopted a literature search approach to retrieve relevant articles which were subjected to keyword analysis to enable categorization of extant BIM for FM research into appropriate sub-domains. A qualitative analysis of 94 BIM for FM-related literature was carried out in addition to a review of 9 capital project-related articles, leading to the establishment of research trends, gaps and future directions.

The review found that research in the BIM-FM integration field is predominantly technology and process-oriented, with less attention paid to people or organizational aspects. Therefore, there is a need for expanding the knowledge base in this direction. Several future research directions were identified to lay the foundations for research on BIM application to FM in large capital projects and other application areas for interested researchers. These future directions were categorized under the identified sub-domains of the field and mapped onto two generic activities, i.e. technical integration and business integration, involved in technology adoption by organizations.

The main contribution of this study is the categorization of existing research on BIM for FM, leading to the identification of research gaps concerning the initiation and implementation of BIM for FM in large capital projects. As a secondary benefit, this study has validated some sub-domains of the BIM for the FM research field identified in previous review papers using an empirical approach. This validation of defined sub-domains is useful for an emerging research field as it provides a common understanding of trends and specific application areas.

The purpose of this paper is to investigate and improve a new method of unstructured rotational dynamic overset grids, which can be used to simulate the unsteady flows around rotational parts of aircraft.

The computational domain is decomposed into two sub-domains, namely, the rotational sub-domain which contains the rotational boundaries, and the stationary sub-domain which contains the remainder flow field including the stationary boundaries. The artificial boundaries and restriction boundaries are used as the restriction condition to generate the entire computational grid, and then the overset grids are established according to the radius parameters of artificial boundaries set previously. The deformation of rotational boundary is treated by using the linear spring analogy method which is suitable for the dynamic unstructured grid. The unsteady Navier-Stokes/Euler equations are solved separately in the rotational sub-domain and stationary sub-domain, and data coupling is accomplished through the overlapping area. The least squares method is used to interpolate the flow variables for the artificial boundary points with a higher calculating precision. Implicit lower-upper symmetric-Gauss-Seidel (LU-SGS) time stepping scheme is implemented to accelerate the inner iteration during the unsteady simulation.

The airfoil steady flow, airfoil pitching unsteady flow, three-dimensional (3-D) rotor flow field, rotor-fuselage interaction unsteady flow field and the flutter exciting system unsteady flow field are numerically simulated, and the results have good agreements with the experimental data. It is shown that the present method is valid and efficient for the prediction of complicated unsteady problems which contain rotational dynamic boundaries.

The results are entirely based on computational fluid dynamics (CFD), and the 3D simulations are based on the Euler equations in which the viscous effect is ignored. The current work shows further applicable potential to simulate unsteady flow around rotational parts of aircraft.

The current study can be used to simulate the two-dimensional airfoil pitching, 3-D rotor flow field, rotor-fuselage interaction and the flutter exciting system unsteady flow. The work will help the aircraft designer to get the unsteady flow character around rotational parts of aircraft.

A new type of rotational dynamic overset grids is presented and validated, and the current work has a significant contribution to the development of unstructured rotational dynamic overset grids.

The purpose of this paper is to study the saturation and nonlinear performance of magnetic field in the air gap of switched reluctance motor (SRM).

The analytical method of sub-domain combined with the saturation compensation method is used to determine the nonlinear distribution of air gap magnetic field in SRM. Also, the resolutions of the two-dimensional (2D) Laplace’s equation and Poisson’s equation in polar coordinates are used to obtain the simplified expression of magnetic flux density.

For verifying the effectiveness of analytical model, the results are compared with those obtained from the 2D finite element method (FEM). The influence of magnetic saturation is taken into account by associating the sub-domain analysis result with the nonlinear B-H properties of stator and rotor iron. The magnetic flux density in radial and tangential direction considering the saturation effect may be calculated accurately. It can be seen that one can easily determine the linear analytical results accurately, whereas it is difficult to determine the magnetic flux density with saturation influence; especially at some local positions, there is a larger difference between analytical and FE model due to the complex boundary conditions.

This paper presents the development and optimization design of high-performance SRM.

The magnetic saturation may be taken into account for the SRM and analytical models support to simulated system performance.

The work of Michel Foucault is taken as inspiration for a study of the organizational field of asylums, prisons, orphanages, and other carceral organizations operating in New York City in 1888. Foucault argues that institutional power is organized into dually ordered system of truth and power. Using text data describing the clients and institutional technologies (organizational “power signatures”) of 168 organizations, we apply structural equivalence methods to unpack speech activity, showing that as Foucault suggests, there may be dually ordered sub-domains of truth and power that help define the underlying logic of this institutional field.

The aim of this paper is to assess the ability of a stress-blended eddy simulation (SBES) turbulence model to predict the performance of a three-straight-bladed vertical axis wind turbine (VAWT). The grid sensitivity study is conducted to evaluate the simulation accuracy.

The unsteady Reynolds-averaged Navier–Stokes equations are solved using the computational fluid dynamics (CFD) technique. Two types of grid topology around the blades, namely, O-grid (OG) and C-grid (CG) types, are considered for grid sensitivity studies.

With regard to the power coefficient (Cp), simulation results have shown significant improvements of predictions using compared to other turbulence models such as the k-e model. The Cp distributions predicted by applying the CG mesh are in good agreement with the experimental data than that by the OG mesh.

The current study provides some new insights of the use of SBES turbulence model in VAWT CFD simulations.

The SBES turbulence model can significantly improve the numerical accuracy on predicting the VAWT performance at a lower tip speed ratio (TSR), which other turbulence models cannot achieve. Furthermore, it has less computational demand for the finer grid resolution used in the RANS-Large Eddy Simulation (LES) “transition” zone compared to other hybrid RANS-LES models.

To authors’ knowledge, this is the first attempt to apply SBES turbulence model to predict VAWT performance resulting for accurate CFD results. The better prediction can increase the credibility of computational evaluation of a new or an improved configuration of VAWT.