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The Internet has evolved, prompted in part by new Web 2.0 technologies, to become a more widespread platform for interaction, communication, and activism. Virtual communities, or groups of people informally bound together by shared expertise, synthesise this Internet evolution and the Web 2.0 technology. Users increasingly want to engage online with one another and with organisations of all kinds. These novel Internet‐based technologies dominate the new business models of the digital economy giving companies radical new ways to harvest the talents of innovators working outside corporate boundaries. One of the most illustrative examples of this new trend is the Open Source Software (OSS) projects development. This paper aims to analyse the structure and topology of the virtual community supporting one of the most successfully OSS projects, Linux. The objective is to provide conclusions for being successful in the development of future virtual communities. As companies learn to manage these virtual communities, they will develop smarter and faster ways to create value through them.

The interactions of the virtual community members of an ARM‐embedded Linux project website is analysed through social network analysis techniques. The participants' activity is studied and some conclusions about the participation features are obtained using the Gini coefficient. In particular, a participation inequality behaviour or a concentration on a small number of developers is clearly observed.

The paper deals with the guidelines that virtual communities should follow to be successful. Results about the structure of a successful virtual community and its time evolution are provided to determine the mentioned guidelines.

The research is limited to a particular virtual community engaged with the development of the ARM‐embedded Linux OSS. Other successful virtual communities can be analysed, and the conclusions could be compared. Anyway, the proposed analysis methodology can be extended to other virtual communities.

The paper fulfils the development and features of Internet virtual communities to be successful. Results have important implications over the development of new software business models based on virtual communities and open source software. Contributions about the best organisation of virtual communities leading to a successful development of the underlying project are presented.

The purpose of this paper is to present a remote lab and a web‐based teaching environment which provides access for remote control of Digital Signal Processors (DSP device) and real instrumentation. The framework, named eDSPLab, has been designed using LabVIEW for debugging and testing Digital Signal Processing (DSP) experiments in a real lab without physical and temporal restrictions, and it has been integrated as a service in a modern e‐learning application domain and a Learning Management System (LMS) to reinforce its utility.

A literature review is presented to provide background to the progressive role that DSP and DSP devices play in Information and Communications Technology (ICT)‐demanded job profiles, and the role that a computer‐mediated environment plays in modern teaching methodologies. The web service access control architecture is defined.

The paper provides new insights into the use of the Internet for laboratory teaching.

This research was limited to one particular remote lab. Results could be extended if students' perceptions and their acceptance of the new e‐learning technology are examined using an information system theory, such as the Technology Acceptance Model (TAM).

This paper fulfils a need for adapting the teaching methodology applied in an undergraduate Advanced Microprocessor course of the Telecommunication Engineering degree at the University of Seville, Spain, allowing the development of laboratory experiments anywhere and anytime, avoiding one of the problems in lab training: the low number of laboratory working places in relation to the high number of enrolled students. The system developed has been successfully used during the last academic years in a course involving more than 200 students.

The purpose of this paper is to study the development of novel multiphase induction motor (MPIM) with copper die cast rotor in the drive system of electric propulsion vehicles (EPV). It is estimated that the manufacturers are concerned about high torque,Efficiency, motor life, energy conservation and high thermal tolerance. To ensure maximum torque and efficiency with multiphase winding and copper die cast technology to increasing high thermal tolerance, life, energy conversations. On other hand, it is very important of EPV application.

The focus of the investigation is threefold: the modified method carried out on MPIM both stator and rotor can overcome the current scenario problem facing by electric vehicles manufacture and developed perfect suitable electric motor for EPV applications. The design and simulation carried out finite element method (FEM) that was more accurate calculations. Finally developed prototype model of MPIM with copper die cast are discussed with conventional three phase Die casting Induction motor.

The paper confirmed the multiphase copper die-cast rotor induction motor (MDCrIM) is providing better performance than conventional motor. Proposed motor can bring additional advantage like heat tolerances, long life and energy conversations.

The experiments confirmed the MDCIM suitable for EPV Applications. The modified MDCIM of both stator and rotor are giving better result and good performance compared to conventional method.

A large variety of online communities have emerged during the last years as a result of the challenges faced by both the business and scientific worlds. This trend has also been promoted by the development of internet and new Web 2.0 technologies. In this context, this paper is focused on the determinants of success of online communities. But, as a difference from other studies, these determinants are analyzed from the social network analysis perspective. Several constructs related to the community organization as a social network are proposed and their interrelations are hypothesized in a general research framework. The obtained results test the proposed model providing the most relevant antecedents of the project success.

A case study based on Linux ports to non‐conventional processor and environments is used to test the proposed model. Structural equation modeling analysis is used to validate the structural proposed model.

The main antecedents of online communities' success, quantifying the strength of the relation through the standardized path coefficients.

The research is limited to a particular set of online communities engaged with the development of the non‐conventional Linux ports. However, they constitute a representative set of communities in the field of the open source projects (OSS) development, which are typically developed using a community of support.

This paper fulfils the main antecedents causing the successful development of Internet virtual communities. Instead of using sources of data coming from users' surveys, this study employs community interactions as a source of data. Results have important implications over the development of online communities, like software business models based on virtual communities and open source software.

Web sites are typically designed attending to a variety of criteria. However, web site structure determines browsing behavior and way‐finding results. The aim of this study is to identify the main profiles of web sites' organizational structure by modeling them as graphs and considering several social network analysis features.

A case study based on 80 institutional Spanish universities' web sites has been used for this purpose. For each root domain, two different networks have been considered: the first is the domain network, and the second is the page network. In both cases, several indicators related to social network analysis have been evaluated to characterize the web site structure. Factor analysis provides the statistical methodology to adequately extract the main web site profiles in terms of their internal structure.

This paper allows the categorization of web site design styles and provides general guidelines to assist designers to better identify areas for creating and improving institutional web sites. The findings of this study offer practical implications to web site designers for creating and maintaining an effective web presence, and for improving usability.

The research is limited to 80 institutional Spanish universities' web sites. Other institutional university web sites from different countries can be analyzed, and the conclusions could be compared or enlarged.

This paper highlights the importance of the internal web sites structure, and their implications on usability and way‐finding results. As a difference to previous research, the paper is focused on the comparison of internal structure of institutional web sites, rather than analyzing the web as a whole or the interrelations among web sites.

This paper aims to investigate three low-evaluation-budget optimization techniques: output space mapping (OSM), manifold mapping (MM) and Kriging-OSM. Kriging-OSM is an original approach having high-order mapping.

The electromagnetic device to be optimally sized is a five-phase linear induction motor, represented through two levels of modeling: coarse (Kriging model) and fine.The optimization comparison of the three techniques on the five-phase linear induction motor is discussed.

The optimization results show that the OSM takes more time and iteration to converge the optimal solution compared to MM and Kriging-OSM. This is mainly because of the poor quality of the initial Kriging model. In the case of a high-quality coarse model, the OSM technique would show its domination over the other two techniques. In the case of poor quality of coarse model, MM and Kriging-OSM techniques are more efficient to converge to the accurate optimum.

Kriging-OSM is an original approach having high-order mapping. An advantage of this new technique consists in its capability of providing a sufficiently accurate model for each objective and constraint function and makes the coarse model converge toward the fine model more effectively.

Intelligent transportation systems (ITS) are defined as new infrastructures that combine people, roads and vehicles over the basis of modern embedded systems with enhanced digital connectivity. ITS is fast becoming a reality, favored in their development by the use of the internet. The purpose of this paper is to analyze the feasibility of road‐traffic management systems, using the internet as the communication link.

A literature review is presented to give a background in the progressive role that ITS and road safety and control applications play in society. The combination of internet and the ITS architecture is covered, and an electronic prototype providing web services for road‐traffic management is designed as an example. The scope of road traffic security research is extensive, and the use of artificial vision systems in road‐traffic analysis (technology which is on the basis of the developed prototype) is also discussed. The hardware and software characteristics of the prototype are defined.

The paper provides new insights into the use of the internet for road‐traffic management applications.

The research is limited to one particular road‐traffic management system. Results could be extended if more real equipments were analyzed. Also, end‐users' perception and their acceptance of the new technology could be examined using an information system theory like the technology acceptance model.

The paper shows the utility of the internet in the development of novel ITS.

The purpose of this paper is to estimate tax evasion and its impact on progressivity, redistribution and the measurement of inequality, using microdata from the Spanish income tax for 2001-2004.

The approach follows Feldman and Slemrod (2007) by exploiting the relation of charitable donations with the composition of income but introduces two methodological innovations, which could be useful for further studies: correction for sample selection with a Heckman two-step setting and the calculation of different evasion rates for top incomes with an interaction term.

Evasion in capital incomes was significant throughout these years. Financial incomes were reported at around 50-70 per cent of their real value, with the lowest estimates corresponding to the top decile. Revenues from fixed capital display similarly low compliance rates for the top 10 per cent. Tax evasion in self-employment incomes (direct assessment) is estimated at 20 per cent for 2001. Mostly because of a composition effect, this means that fraud was higher at the top of the income distribution, thus having a regressive impact. Inequality statistics and top income concentration estimates should, therefore, be revised upwards.

This is the first paper to estimate the distributive impacts of tax evasion in Spain, and one of very few internationally.

The objective of this systematic literature review (SLR) is to explore the current state of research in the field of household finance (HF). This study aims to summarize the existing research to highlight the importance of household finance in a nation’s economy. By exploring all conceptual and applied implications of HF, this study projects directions for future research to develop a comprehensive understanding of the subject.

This SLR is based on 112 articles published in peer-reviewed journals between 2006 and 2020 (Table 3). The methodology comprises five steps, namely, formulation of research questions, identification of studies, their selection and evaluation, analyses and syntheses and presentation of results.

The findings of this study show that studies on HF are gradually increasing worldwide with the USA registering the highest number of published research on the topic during the period under scrutiny. Notwithstanding the increasing attention and research on HF, empirical research in emerging economies is lagging. Additionally, this study finds that HF structure presents a perfect setting to understand how households compose their financial portfolio, make financial decisions and what factors influence their decisions.

This study is an SLR – an accurate and accepted method of reviewing available literature on a selected subject. However, the selection of inclusion and exclusion criteria depends on the researchers’ rationale which might lead to research bias. This should be considered an inherent limitation of SLR.

By synthesizing the contents of extant literature, this study presents important insights into HF. This study underlines the most discussed topics in the domain and identifies potential investigation areas. This study gives the knowledge of leading articles, authors and journals and informs scholars and academicians about the areas that need further investigation by portraying the complete picture of the subject in a systematic manner. Further, this study highlights that households make suboptimal financial decisions that affect their financial well-being. To reduce the adverse impacts of these decisions, policymakers and financial institutions must take steps to improve households’ use of formal financial markets. Household decisions can be reformed by enhancing consumers’ knowledge about financial products and services. Furthermore, households can be served better by offering customization in traditional financial products.

This study synthesizes the main findings of selected literature on HF. The expansion of studies on HF has generated the need to review the existing literature in a systematic manner. To the researchers’ best knowledge, this SLR is the first thorough study of available articles in the HF domain. This study presents the scope of future research by highlighting numerous aspects and functions of HF.

The purpose of this article is to treat the nonlinear optimal control problem in EV traction systems which are based on 5-phase induction motors. Five-phase permanent magnet synchronous motors and five-phase asynchronous induction motors (IMs) are among the types of multiphase motors one can consider for the traction system of electric vehicles (EVs). By distributing the required power in a large number of phases, the power load of each individual phase is reduced. The cumulative rates of power in multiphase machines can be raised without stressing the connected converters. Multiphase motors are also fault tolerant because such machines remain functional even if failures affect certain phases.

A novel nonlinear optimal control approach has been developed for five-phase IMs. The dynamic model of the five-phase IM undergoes approximate linearization using Taylor series expansion and the computation of the associated Jacobian matrices. The linearization takes place at each sampling instance. For the linearized model of the motor, an H-infinity feedback controller is designed. This controller achieves the solution of the optimal control problem under model uncertainty and disturbances.

To select the feedback gains of the nonlinear optimal (H-infinity) controller, an algebraic Riccati equation has to be solved repetitively at each time-step of the control method. The global stability properties of the control loop are demonstrated through Lyapunov analysis. Under moderate conditions, the global asymptotic stability properties of the control scheme are proven. The proposed nonlinear optimal control method achieves fast and accurate tracking of reference setpoints under moderate variations of the control inputs.

Comparing to other nonlinear control methods that one could have considered for five-phase IMs, the presented nonlinear optimal (H-infinity) control approach avoids complicated state-space model transformations, is of proven global stability and its use does not require the model of the motor to be brought into a specific state-space form. The nonlinear optimal control method has clear implementation stages and moderate computational effort.

In the transportation sector, there is progressive transition to EVs. The use of five-phase IMs in EVs exhibits specific advantages, by achieving a more balanced distribution of power in the multiple phases of the motor and by providing fault tolerance. The study’s nonlinear optimal control method for five-phase IMs enables high performance for such motors and their efficient use in the traction system of EVs.

Nonlinear optimal control for five-phase IMs supports the deployment of their use in EVs. Therefore, it contributes to the net-zero objective that aims at eliminating the emission of harmful exhaust gases coming from human activities. Most known manufacturers of vehicles have shifted to the production of all-electric cars. The study’s findings can optimize the traction system of EVs thus also contributing to the growth of the EV industry.

The proposed nonlinear optimal control method is novel comparing to past attempts for solving the optimal control problem for nonlinear dynamical systems. It uses a novel approach for selecting the linearization points and a new Riccati equation for computing the feedback gains of the controller. The nonlinear optimal control method is applicable to a wider class of dynamical systems than approaches based on the solution of state-dependent Riccati equations.