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1 – 10 of 21Mohsen Rostami, Peyman Naderi and Abbas Shiri
The aim of this paper is to propose the model for analyzing the electromagnetic performances of permanent magnet vernier machines (PMVMs) under healthy and faulty conditions.
Abstract
Purpose
The aim of this paper is to propose the model for analyzing the electromagnetic performances of permanent magnet vernier machines (PMVMs) under healthy and faulty conditions.
Design/methodology/approach
The model uses interconnected reluctance network formed based on the geometrical approximations to predict magnetic performances of the machine. The network consists of several types of reluctances for modeling different parts of machine. Applying Kirchhoffs laws in the network and the machine windings, magnetic and electrical equations are obtained, respectively. To construct the model system of equations, the electrical equation is converted into algebraic form by using the trapezoidal technique. Moreover, the system of equations must be solved by Newton–Raphson method in each step-time because of considering the core saturation effect.
Findings
The proposed model is developed based on the modified magnetic equivalent circuit (MEC) method, in which the number of flux paths in different parts of the machine can be arbitrary selected. The saturation effect, skewed slots, the desired machine geometrical parameters and various winding arrangements are included in the proposed model; therefore, it can evaluate the time and space harmonics in modeling the PMVMs. Furthermore, a pattern for inter-turn fault detection is extracted from the stator current spectrum. Finally, 2 D-finite element method (FEM) and 3 D-FEM analysis are carried out to evaluate and verify the results of the proposed MEC model.
Originality/value
Generally, the element numbers have important role in modeling the machine and calculating its performance. Hence, the proposed MEC model’s capability to choose desired number of flux paths is advantage of this paper. Moreover, the developed MEC can be used for analyzing several electrical machines, including other types of vernier machines, with simple modification.
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Mohsen Rostami, Peyman Naderi and Abbas Shiri
The purpose of this paper is to propose a saturable model based on the magnetic equivalent circuit (MEC) for evaluating the electromagnetic performance of the variable area…
Abstract
Purpose
The purpose of this paper is to propose a saturable model based on the magnetic equivalent circuit (MEC) for evaluating the electromagnetic performance of the variable area resolver.
Design/methodology/approach
The equivalent circuit is developed where three different reluctance types are used to calculate permeances based on geometrical approximations. The proposed model typically has two types of equations, including the magnetic and electrical equations. The magnetic and electrical equations are related to the resolver core and the windings, respectively. Applying the well-known trapezoidal method, the magnetic and electrical equations can be simultaneously solved. A nonlinearity of the magnetic equations, the algebraic equations system, which is obtained from Kirchhoff’s laws, should be solved by the Newton-Raphson technique in each step-time.
Findings
The flexible MEC model, in which the number of flux tubes in different parts of the resolver can be arbitrarily selected, is proposed to analyze the variable reluctance resolver. Besides, the design parameters such as geometrical dimensions, windings arrangement and a number of the rotor saliencies can be chosen as desired. To consider the effect of time harmonics, a new nonlinear function is used for the core magnetization. Furthermore, different winding layouts can be implemented in the model to take space harmonics into account. The model obtained results are compared with the finite element method in terms of accuracy and simulation time.
Originality/value
Generally, the accuracy of the predictions in the MEC method is dependent on the number of flux tubes; therefore, the flexibility of the proposed MEC model in its capability to choose the desired number of flux paths is the advantage of this work. Moreover, the proposed model can analyze both wound and saliency rotor resolvers by changing the design parameters.
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Mousa Pazhuhan and Narges Shiri
This paper aims to identify and determine regional tourism axes in Hormozgan Province, Iran, as a region with significant potential
Abstract
Purpose
This paper aims to identify and determine regional tourism axes in Hormozgan Province, Iran, as a region with significant potential
Design/methodology/approach
The research method is quantitative and uses the fuzzy accreditation tool and TOPSIS model; the identification, determination and ranking of regional tourism axes have been performed by analyzing the spatial distribution of tourism attractions in the GIS environment.
Findings
The results show that given the capacities of Hormozgan Province, at least 15 axes are recognizable. This paper highlights regional tourism planning as a tool for urban and rural socio-economic development in potential provinces such Hormozgan.
Originality/value
This study provides a number of practical implications for regional tourism development as follows: it identifies some of the most important potential axes in Hormozgan Province, which can be considered as investment areas in the national and regional tourism development strategy. The spatial results of this study could be embedded in all urban and rural developmental plans in the province. Tourism investment should shift its spatial concentration from the spot approach, especially islands and cities, to the axis approach while equipping those axes as comprehensive spatial strategic regional tourism plans. Sectoral tourism in each sector including sports, economy and nature could be planned as if sectoral institutions and organizations are going to develop their own tourism goals.
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Mehdi Alipour‐Hafezi, Abbas Horri, Ali Shiri and Amir Ghaebi
The purpose of this paper is to provide an overview of the existing interoperability models in digital libraries and to introduce related projects in each model.
Abstract
Purpose
The purpose of this paper is to provide an overview of the existing interoperability models in digital libraries and to introduce related projects in each model.
Design/methodology/approach
The study starts from searching various databases with a combination of important keywords in the field, such as interoperability, digital library, meta‐searching and cross‐searching. The study follows up with describing related digital library projects in the field of technical interoperability. The projects are described under three main categories, Federated, Harvesting and Gathering.
Findings
The study shows that most of the studied projects are located in the USA and also most of the digital library projects use OAI protocol and the harvesting model in order to be technically interoperable. Also, the results of the study showed that the projects mostly paid attention to metadata interoperability and only a few mentioned full‐text interoperability issues.
Originality/value
The paper makes an original contribution of exploring an area (interoperability models in digital libraries), that is at the forefront of discussion in libraries worldwide.
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This is an attempt to introduce proactive changes when creating and providing intellectual access in order to convince catalogers to become more social catalogers then they have…
Abstract
Purpose
This is an attempt to introduce proactive changes when creating and providing intellectual access in order to convince catalogers to become more social catalogers then they have ever been in the past.
Approach
Through a brief review and analysis of relevant literature a definition of social cataloging and social cataloger is given.
Findings
User contributed content to library catalogs affords informational professionals the opportunity to see directly the users’ perceptions of the usefulness and about-ness of information resources. This is a form of social cataloging especially from the perspective of the information professional seeking to organize information to support knowledge discovery and access.
Implications
The user and the cataloger exercise their voice as to what the information resources are about, which in essence is interpreting the intentions of the creator of the resources, how the resource is related to other resources, and perhaps even how the resources can be, or have been, used. Depending on the type of library and information environment, the weight of the work may or may not fall equally on both user and cataloger.
Originality/value
New definitions of social cataloging and social cataloguing are offered and are linked back to Jesse Shera’s idea of social epistemology.
Mahdi Salehi, Mahmoud Mousavi Shiri and Mohammad Bolandraftar Pasikhani
Financial distress is the most notable distress for companies. During the past four decades, predicting corporate bankruptcy and financial distress has become a significant…
Abstract
Purpose
Financial distress is the most notable distress for companies. During the past four decades, predicting corporate bankruptcy and financial distress has become a significant concern for the various stakeholders in firms. This paper aims to predict financial distress of Iranian firms, with four techniques: support vector machines, artificial neural networks (ANN), k-nearest neighbor and na
i
ve bayesian classifier by using accounting information of the firms for two years prior to financial distress.
Design/methodology/approach
The distressed companies in this study are chosen based on Article 141 of Iranian Commercial Codes, i.e. accumulated losses exceeds half of equity, based on which 117 companies qualified for the current study. The research population includes all the companies listed on Tehran Stock Exchange during the financial period from 2011-2012 to 2013-2014, that is, three consecutive periods.
Findings
By making a comparison between performances of models, it is concluded that ANN outperforms other techniques.
Originality/value
The current study is almost the first study in Iran which used such methods to analyzing the data. So, the results may be helpful in the Iranian condition as well for other developing nations.
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Hasan Boudlaie, Mohammad Hosein Kenarroodi, Razieh Sadraei and Vahid Jafari-Sadeghi
Entrepreneurs’ decision-making for detecting, evaluating and utilising opportunities across international borders is one of the main subjects of international entrepreneurship…
Abstract
Entrepreneurs’ decision-making for detecting, evaluating and utilising opportunities across international borders is one of the main subjects of international entrepreneurship research. This study aims to argue that recognising and classifying international entrepreneurship opportunities facilitate the decision-making process. To do such a thing, a multi-layer decision-making approach focusses on the industrial sector of the Kish free zone. In the first stage, the data will be collected by a questionnaire survey of entrepreneurial companies in the industry field and the main international entrepreneurship opportunities will be identified. In the second stage, the importance and relationship between the opportunities will be evaluated based on the identified opportunities. Eventually, in the last stage, the relationship and the importance of the opportunities will be determined by proposing and using a multi-layer decision-making approach. In conclusion, the prioritised international entrepreneurship opportunities will be presented.
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Currently, the evaluation of scientific performance of universities is one of the important indicators in various ranking systems. One way to evaluate the academic performance of…
Abstract
Purpose
Currently, the evaluation of scientific performance of universities is one of the important indicators in various ranking systems. One way to evaluate the academic performance of universities is to analyze the scientific documents of universities in reputable international databases. The purpose of this article is to analyze and evaluate the scientific publications of Alzahra University (Iran) as the top 100–200 universities during 1986–2019.
Design/methodology/approach
This study was performed using bibliometrics and visualization techniques. The Scopus database was used to collect data. Affiliation search and advanced search were used to retrieve the data. Excel, VOSviewer and CRExplorer software were used to analyze the data.
Findings
The results showed that the scientific publications and received citations by Alzahra University documents during the time have been upward. At the national level, it was the most scientific collaboration with researchers at the University of Tehran. Also at the international level, the most scientific collaboration has been with the United States, Canada and Germany. In total, 80% of scientific publications were published by 20% of authors. Also, 70% of the highly cited articles were published in journals with quartile 1. Finally, clustering results showed that Alzahra University's scientific publications are in five main categories, including “chemistry,” “physics,” “biology,” “psychology and educational sciences” and “accounting sciences, management, and computer science.”
Originality/value
This study could be a good model for evaluating the performance of scientific productions of universities and scientific institutions with bibliometrics and visualization approaches.
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Mohanad Mustafa and As'ad Ghanem
This article aims to analyse the Israeli negotiation strategy in reference to the theoretical frameworks of reconciliation and settlement. It focuses on the Israeli‐Palestinian…
Abstract
Purpose
This article aims to analyse the Israeli negotiation strategy in reference to the theoretical frameworks of reconciliation and settlement. It focuses on the Israeli‐Palestinian negotiation experience over the past three years, or since Netanyahu was elected Prime Minister of the Israeli Government in 2009.
Design/methodology/approach
Theoretical literature provides two hypothetical frameworks for resolution of conflicts: a political settlement; and reconciliation between parties to the conflict. This article argues that Israel's vision of conflict resolution effectively attempts to integrate both hypothetical frameworks by proposing a political settlement for Palestinians in return for obtaining reconciliation from them. To analyse this strategy, this article explores the Israeli political discourse over the past three years, as well as Israel's vision of the conflict resolution as is manifest in this discourse.
Findings
The article argument is based on the indication that willingness of a party to reach a settlement is met with reconciliation from the other party to the conflict. A party's insistence on offering a settlement and attaining reconciliation is associated with power relations between both parties. To maintain its powerful position, the stronger party usually demands reconciliation from the weaker party, at the same time presenting a settlement that implies a political, not moral, recognition of the weaker party with a view to dispossess it from its moral logic in the conflict.
Originality/value
An assessment of the Israeli political discourse over the past three years indicates that Israel is implementing a compound negotiation strategy to resolve the conflict. The strategy entails settlement and reconciliation components. Israel wishes to deal with Palestinians through a political settlement. On the other hand, Israel wants the Palestinians to deal with it through the reconciliation process.
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Abstract
Purpose
Many higher education institutions are investigating the possibility of developing predictive student success models that use different sources of data available to identify students that might be at risk of failing a course or program. The purpose of this paper is to review the methodological components related to the predictive models that have been developed or currently implemented in learning analytics applications in higher education.
Design/methodology/approach
Literature review was completed in three stages. First, the authors conducted searches and collected related full-text documents using various search terms and keywords. Second, they developed inclusion and exclusion criteria to identify the most relevant citations for the purpose of the current review. Third, they reviewed each document from the final compiled bibliography and focused on identifying information that was needed to answer the research questions
Findings
In this review, the authors identify methodological strengths and weaknesses of current predictive learning analytics applications and provide the most up-to-date recommendations on predictive model development, use and evaluation. The review results can inform important future areas of research that could strengthen the development of predictive learning analytics for the purpose of generating valuable feedback to students to help them succeed in higher education.
Originality/value
This review provides an overview of the methodological considerations for researchers and practitioners who are planning to develop or currently in the process of developing predictive student success models in the context of higher education.
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