bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling of a VSC-based multi-terminal HVDC network for dynamic stability analysis
Authors: Shinoda Kosei , Guillaud Xavier , Bacha Seddik , Benchaib Abdelkrim , Francois Bruno 
Published: January 2017

Purpose
Self-commuted voltage source converter (VSC) can significantly extend the flexibility and operability of an HVDC system and be used to implement the concept of multi-terminal HVDC (MTDC) grid. To take full advantage of MTDC systems, its overall behaviour must be characterized in quasi static and dynamic states. Based on the numerous literatures, a dedicated two-level VSC model and its local controllers and DC grid voltage regulators are developed for this purpose. Furthermore, the requirement of the system to guarantee all the physical constrains must be well assessed and concrete demonstrations must be provided by numerical simulations.

Design/methodology/approach
First, a two-level VSC model and its local controllers and DC grid voltage regulators are developed. Then, DC cable models are investigated and their characteristics are assessed in the frequency domain. Those developed models are combined to form a three-terminal HVDC grid system on Matlab/Simulink platform. To analyze the stability of this electrical system, the dynamics of the system against variations of power dispatch are observed.

Findings
To analyze the stability of this electrical system, the dynamics of the system against variations of power dispatch are observed. The differences in the DC grid voltage dynamics and the power flow of the converter stations coming from the embedded primary controls are analysed, and the technical requirements for both cases are assessed.

Originality/value
In this paper, the dynamic stability of an MTDC system has been analysed and assessed through an adequate simulation model, including its control scheme and the cable models. The interest of the improved PI model for cables is highlighted.
Design of an energy storage system based on vanadium redox flow battery considering a simplified model of VRB
Authors: Lei Jiazhi , Gong Qingwu , Ye Jun 
Published: January 2017

Purpose
This paper aims to propose a simplified model of vanadium redox flow batteries (VRBs) for VRB energy storage system (ESS) design considering the operational characteristics of VRB, and a VRB ESS, considering the low terminal voltage of VRB, was presented.

Design/methodology/approach
According to the designed topology of VRB ESS and the simplified model of VRB, a small perturbation analysis method was used to establish the transfer function of VRB ESS, and the controller parameters of VRB ESS under constant charging and discharging current were designed.

Findings
Test results have demonstrated that this designed VRB ESS has fast response, small overshoot, strong adaptation and high steady precision, which strongly verified the reasonable design.

Practical implications
This simplified model of VRB can be suitably used for VRB ESS design. This designed VRB ESS realized the bidirectional power flow of VRB and AC grid. In this designed VRB ESS, phase-shifted full-bridge converter and a single-phase inverter were used and VRB was charged and discharged under constant current.

Originality/value
The paper presents a topology of VRB ESS which can realize the bidirectional power flow of VRB and AC grid. Considering the complexity of VRB model, a simplified model of VRB was proposed for the controller parameters design of VRB ESS, and this method can be used in application.
Detection of time-varying inter-turn short-circuit in a squirrel cage induction machine by means of generalized regression neural network
Authors: Pietrowski Wojciech 
Published: January 2017

Purpose
Diagnostics of electrical machines is a very important task. The purpose of this paper is the presentation of coupling three numerical techniques, a finite element analysis, a signal analysis and an artificial neural network, in diagnostics of electrical machines. The study focused on detection of a time-varying inter-turn short-circuit in a stator winding of induction motor.

Design/methodology/approach
A finite element method is widely used for the calculation of phase current waveforms of induction machines. In the presented results, a time-varying inter-turn short-circuit of stator winding has been taken into account in the elaborated field-circuit model of machine. One of the time-varying short-circuit symptoms is a time-varying resistance of shorted circuit and consequently the waveform of phase current. A general regression neural network (GRNN) has been elaborated to find a number of shorted turns on the basis of fast Fourier transform (FFT) of phase current. The input vector of GRNN has been built on the basis of the FFT of phase current waveform. The output vector has been built upon the values of resistance of shorted circuit for respective values of shorted turns. The performance of the GRNN was compared with that of the multilayer perceptron neural network.

Findings
The GRNN can contribute to better detection of the time-varying inter-turn short-circuit in stator winding than the multilayer perceptron neural network.

Originality/value
It is argued that the proposed method based on FFT of phase current and GRNN is capable to detect a time-varying inter-turn short-circuit. The GRNN can be used in a health monitoring system as an inference module.
Model refinements of transformers via a subproblem finite element method
Authors: Dular Patrick , Kuo-Peng Patrick , Ferreira da Luz Mauricio Valencia , Krahenbuhl Laurent 
Published: January 2017

Purpose
This paper aims to develop a methodology for progressive finite element (FE) modeling of transformers, from simple to complex models of both magnetic cores and windings.

Design/methodology/approach
The progressive modeling of transformers is performed via a subproblem (SP) FE method. A complete problem is split into SPs with different adapted overlapping meshes. Model refinements are performed from ideal to real flux tubes, one-dimensional to two-dimensional to three-dimensional models, linear to nonlinear materials, perfect to real materials, single wire to volume conductor windings and homogenized to fine models of cores and coils, with any coupling of these changes.

Findings
The proposed unified procedure efficiently feeds each SP via interface conditions (ICs), which lightens mesh-to-mesh sources transfers and quantifies the gain given by each refinement on both local fields and global quantities, with a clear view on its significance to justify its usefulness, if any. It can also help in education with a progressive understanding of the various aspects of transformer designs.

Originality/value
Models of different accuracy levels are sequenced with successive additive corrections supported by different adapted meshes. The way the sources act at each correction step, up to the full models with their actual geometries, is given a particular care and generalized, allowing the proposed unified procedure. For all the considered corrections, the sources are always of IC type, thus only needed in layers of FE along boundaries, which lightens the required mesh-to-mesh projections between subproblems.
Design optimization of ferrite assisted synchronous reluctance motor using multi-objective differential evolution algorithm
Authors: V.S. Nagarajan , Mahadevan Balaji , V. Kamaraj , R. Arumugam , Nagarajan Ganesh , S. Srivignesh , M. Suudharshana 
Published: January 2017

PurposeThe purpose of this paper is performance enhancement of ferrite-assisted synchronous reluctance (FASR) motor using multi-objective differential evolution (MODE) algorithm, considering the significant geometric design parameters.Design/methodology/approachThis work illustrates the optimization of FASR motor using MODE algorithm to enhance the performance of the motor considering barrier angular positions, magnet height, magnet axial length, flux barrier angles of the rotor and air gap length. In the optimization routine to determine the performance parameters, generalized regression neural network-based interpolation is used. The results of MODE are validated with multi-objective particle swarm optimization algorithm and multi-objective genetic algorithm.FindingsThe design optimization procedure developed in this work for FASR motor aims at achieving multiple objectives, namely, average torque, torque ripple and efficiency. With multiple objectives, it is essential to give the designer the tradeoff between different objectives so as to arrive at the best design suitable for the application. The results obtained in this work justify the application of the MODE approach for FASR motor to determine the various feasible solutions within the bounds of the design.Research limitations/implicationsAnalysis, design and optimization of synchronous reluctance motor has been explored in detail to establish its potential for variable speed applications. In recent years, the focus is toward the electromagnetic design of hybrid configurations such as FASR motor. It is in this preview this work aims to achieve optimal design of FASR motor using multi-objective optimization approach.Practical/implicationsThe results of this work will supplement and encourage the application of FASR motor as a viable alternate for variable speed drive applications. In addition, the application of MODE to arrive at better design solutions is demonstrated.Originality/valueThe approach presented in this work focuses on obtaining enhanced design of FASR motor considering average torque, torque ripple and efficiency as performance measures. Theposteriorianalysis of optimization provides an insight into the choice of parameters involved and their effects on the design of FASR motor. The efficacy of the optimization routine is justified in comparison with other multi-objective algorithms.
Novel cat swarm optimization algorithm to enhance channel equalization
Authors: D.C. Diana , S.P. Joy Vasantha Rani 
Published: January 2017

Purpose
Adaptive equalization plays an important role in digital communication to reduce the distortions due to inter-symbol interference. An adaptive filter is used as an equalizer model in channel equalization. An adaptive algorithm is the heart of the adaptive filter which finds the optimum coefficients of the filter. The choice of the adaptive algorithm improves the convergence rate and minimizes the mean square error (MSE). This paper aims to propose a cat swarm optimization (CSO)-based adaptive algorithm and its modification to improve the performance of a channel equalizer.

Design/methodology/approach
The input digital training data are transmitted through different channel conditions. A linear transversal filter is used as a channel and equalizer model. The equalizer coefficients are trained by the proposed simplified cat swarm optimization (SCSO) algorithm to find the estimated digital training data.

Findings
The performance of the proposed SCSO algorithm is compared with particle swarm optimization (PSO)-based channel equalization. The improvement in convergence rate and MSE is verified under linear and nonlinear channel conditions with different delay spreads. The optimum parameters of the SCSO are found using simulation-based sensitivity analysis.

Originality/value
This paper analyzes a CSO algorithm for adaptive channel equalization and proposes a SCSO algorithm to identify the optimum coefficients of a transversal equalizer. The seeking mode process is simplified in the proposed SCSO to achieve better performance in channel equalization. The proposed SCSO algorithm guarantees minimum MSE in all independent runs, whereas in PSO, few misses are possible.
A species effect on storm erosion: Invasive sedge stabilized dunes more than native grass during Hurricane Sandy
Authors: Charbonneau Bianca R. , Wootton Louise S. , Wnek John P. , Langley J. Adam , Posner Michael A. 
Published: January 2017

Summary

Vegetation and biogeomorphology are highly coupled in beach dune systems, but plant species effects on abating storm erosion are largely unexplored.

We quantified coastal dune erosion from Hurricane Sandy (October 2012) as a function of pre‐storm system characteristics – dune height, beach width and dominant vegetation stabilizing dunes (native Ammophila breviligulata or invasive Carex kobomugi) at Island Beach State Park, New Jersey, USA. We assessed dune erosion using a combination of pre‐ and post‐Sandy aerial image spatial analyses in ArcGIS and GPS field mapping. Our two erosion metrics are novel, macroscale 2D surface area changes and Dune Crest Transgression, the later of which is measured at the microscale (1 m−1) and analysed using a mixed model incorporating spatial autocorrelation.

We document a species‐specific effect on collision erosion. Although C. kobomugi reduces native diversity and abundance, it may be beneficial for coastal protection, as dunes fronted and stabilized by C. kobomugi suffered less erosion than those dominated by A. breviligulata under the same abiotic conditions.

Dune height and beach width were equal for species prior to the storm and therefore do not account for or confound differences in erosion. Similarly, traditional calculations of erosion with volumetric loss confer these results.

Synthesis and applications. This is the first study to show a species effect on coastal dune erosion. Native Ammophila breviligulata stabilized dune stretches suffered more erosion from Hurricane Sandy than complimentary invasive Carex kobomugi stretches, contradicting anecdotal reports that foredunes stabilized by a shorter statured species are more prone to erosion. This study highlights the importance of vegetation for dune stability and management using two novel metrics for erosion. Our erosion metrics are related to volumetric loss, can be monitored and calculated by managers with or without remote sensing, and can be applied to other systems. Discussions on coastal management of dunes as habitats and protective buffers must include vegetation and the results of this study suggest that not all species are equal with regard to their ability to combat storm erosion. Multidisciplinary studies with applied implications will grow increasingly important as storms continue to grow more frequent, severe and unpredictable with climate change.
Generalization and maintenance of treatment gains in primary progressive aphasia (PPA): a systematic review
Authors: Cadório Inês , Lousada Marisa , Martins Paula , Figueiredo Daniela 
Published: January 2017

AbstractBackgroundCognitive–linguistic treatments and interventions targeting communication have been developed within the context of primary progressive aphasia (PPA), however knowledge about the scope of generalization and maintenance of therapy gains considering PPA subtypes remains scarce and awaits systematic investigation.AimsTo analyse the effects of semantic therapy on generalization and maintenance of treatment outcomes in individuals with PPA, considering its different subtypes.Methods & ProceduresCentral, PubMed, Medline, Web of Knowledge and Scopus were used to retrieve articles of interest. A total of 25 non‐randomized studies published between 2000 and 2016 met the eligibility criteria and therefore were included in this study.Main ContributionThis systematic review provides evidence‐based information for clinical practice in PPA. Generalization and maintenance effects post‐treatment for each PPA variant are analysed and discussed. Several factors are described as important to maximize the scope for generalization and maintenance of treatment gains.Conclusions & ImplicationsGeneralization is particularly hard to achieve in the semantic variant, as in the face of degraded semantic knowledge learning is rigid and context dependent. In contrast, non‐fluent and logopenic variants offer better scope for generalization. Maintenance patterns do not seem to be influenced by PPA subtype, but rather by other factors such as continued practice, treatment length and frequency of sessions. In the future, clinicians should consider the PPA subtype when planning the treatment protocol.
Evaluation of Acute Alcohol Intoxication as the Primary Cause of Death: A Diagnostic Challenge for Forensic Pathologists
Authors: Li Rong , Hu Li , Hu Lingli , Zhang Xiang , Phipps Rebecca , Fowler David R. , Chen Feng , Li Ling 
Published: January 2017

AbstractDeaths caused by acute alcohol intoxication (AAI) remain a major public health issue. This study is retrospective and descriptive: an 8‐year case analysis of deaths due to AAI in Maryland. Study showed that of 150 AAI deaths, the death rate among Hispanics (10.41/100,000 population) was significantly higher than all the non‐Hispanics combined (1.88/100,000 population). The majority of individuals were young adults, overweight, and binge drinkers. The obese group showed significantly lower mean heart and peripheral blood alcohol concentration (BAC) (0.36%, 0.37%) than the normal weight group (0.45%, 0.42%). Based on the PBAC and urine AC ratio, 49.6% deaths likely occurred close to peak phase, followed by postabsorptive phase (31.6%) and absorptive phase (18.8%). Our results indicate that forensic pathologists should evaluate postmortem BAC in the light of individual's age, drinking history, body weight, possible phase of alcohol intoxication, and other autopsy findings when certifying AAI as primary cause of death.
Vitamin D serum levels are cross‐sectionally but not prospectively associated with late‐life depression
Authors: Jovanova O. , Aarts N. , Noordam R. , Carola‐Zillikens M. , Hofman A. , Tiemeier H. 
Published: January 2017

ObjectiveThe evidence for a prospective association of vitamin D deficiency with the occurrence of late‐life depression is limited. We aimed to study the long‐term association between vitamin D serum levels and depression in a large population‐based study of older adults.MethodWe included 3251 participants from the Rotterdam Study, aged 55 and older with 32 400 person‐years follow‐up for depression. Baseline 25‐hydroxyvitamin D (25(OH)D) serum levels were analyzed continuously and categorically. Repeated depressive symptoms' questionnaire assessments were used to assess the change of depressive symptoms. Semistructured psychiatric interviews, and GP records were used to assess incident major depressive disorder according to DSM‐IV criteria.ResultsLow serum vitamin D levels were cross‐sectionally associated with more depressive symptoms. However, low 25(OH)D serum levels were not prospectively associated with change of depressive symptoms (unstandardized beta = 0.02, 95% CI = −0.23; 0.26) or incident MDD (hazard ratio = 0.95, 95% CI = 0.86; 1.05).ConclusionWe observed a cross‐sectional but no prospective association between serum vitamin D levels and depression. A cross‐sectional association in the absence of the longitudinal association can mostly be attributed to reverse causality or residual confounding. Probably, vitamin D deficiency is not an independent risk factor for depression but co‐occurs with late‐life depression.
Abnormal peritoneal regulation of chemokine activation—The role of IL‐8 in pathogenesis of endometriosis
Authors: Sikora Justyna , Smycz‐Kubańska Marta , Mielczarek‐Palacz Aleksandra , Kondera‐Anasz Zdzisława 
Published: January 2017

ProblemEndometriosis is a chronic inflammatory disease associated with an impairment in immune response. Disorders in the peritoneal fluid and ectopic endometrium macrophage populations and their secretory products create a specific microenvironment inducing the development of the disease. The important factors involved in inflammation associated with endometriosis are chemokines, especially interleukin (IL)‐8. For this reason, the current study briefly reviews the role of IL‐8 in the pathogenesis of endometriosis.Method of studyA systematic review was done on all published studies that compared IL‐8 expression and concentration in patients with and without endometriosis to evaluate their potential as biomarkers for the disease.ResultsIL‐8 induces chemotaxis of neutrophils and other immune cells; also, it is a potent angiogenic agent. Most researchers pointed to the increased peritoneal and serum IL‐8 levels and showed correlation with the severity of the disease, size and number of the active lesions. IL‐8 takes part in all processes during the development of the disease: adhesion, invasion, and implantation of ectopic tissue. Additionally, the chemokine plays a role in growth and maintenance of ectopic endometrial tissue directly affecting endometrial cell proliferation. IL‐8 might also protect ectopic cells against death by apoptosis.ConclusionIt may act as an autocrine growth factor in the endometrium and promotes the vicious circle of endometrial cell attachment and, in consequence, may lead to a transformation from acute to chronic inflammation stage.
Results of an allergy educational needs questionnaire for primary care
Authors: Ryan D. , Angier E. , Gomez M. , Church D. , Batsiou M. , Nekam K. , Lomidze N. , Gawlik R. 
Published: January 2017

AbstractIt is well recognized that knowledge of allergic conditions is suboptimal in primary care. The Primary Care Interest Group of the European Academy of Allergy and Clinical Immunology undertook an educational needs survey to better understand what they were and how best to meet them, in the primary care environment. An electronic questionnaire was devised and distributed as widely as possible. A total of 2226 people from 63 countries opened the e‐questionnaire of which 692 provided evaluable responses. In total, 81% were medical doctors with 299 possessing additional qualifications. Self‐declared gaps in knowledge were expressed for most manifestations of allergy with a correspondingly high self‐expressed educational need. The preferred learning modalities were online guidelines (69.6%) and courses (68.8%) followed closely by workshops (68%), structured online modules (63.9%) and small local working groups (59.75%). Podcasts and webinars scored poorly with only 25% expressing these as preferred learning modes although there was an age gradient. The preferred electronic platform was the personal computer (82.6%). A better understanding of the needs of primary care should help guide the design of educational initiatives to meet those needs.
New liposomal doxorubicin nanoformulation for osteosarcoma: Drug release kinetic study based on thermo and pH sensitivity
Authors: Haghiralsadat Fateme , Amoabediny Ghasem , Sheikhha Mohammad Hasan , Zandieh‐doulabi Behrouz , Naderinezhad Samira , Helder Marco N. , Forouzanfar Tymour 
Published: January 2017

A novel approach was developed for the preparation of stealth controlled‐release liposomal doxorubicin. Various liposomal formulations were prepared by employing both thin film and pH gradient hydration techniques. The optimum formulation contained phospholipid and cholesterol in 1:0.43 molar ratios in the presence of 3% DSPE‐mPEG (2000). The liposomal formulation was evaluated by determining mean size of vesicle, encapsulation efficiency, polydispersity index, zeta potentials, carrier's functionalization, and surface morphology. The vesicle size, encapsulation efficiency, polydispersity index, and zeta potentials of purposed formula were 93.61 nm, 82.8%, 0.14, and −23, respectively. Vesicles were round‐shaped and smooth‐surfaced entities with sharp boundaries. In addition, two colorimetric methods for cytotoxicity assay were compared and the IC50 (the half maximal inhibitory concentration) of both methods for encapsulated doxorubicin was determined to be 0.1 μg/ml. The results of kinetic drug release were investigated at several different temperatures and pH levels, which showed that purposed formulation was thermo and pH sensitive.