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This paper aims to propose a method of parametrizing topological transformer model at high flux densities in the core.

The approach proposed is based on terminal voltages and currents measured in a special purpose saturation test whose data are combined with typical saturation curves of grain-oriented electrical steels; the modeling is carried out in the ATPDraw program.

The authors corroborate experimentally the necessity of dividing the zero sequence impedance between all transformer phases and propose a method of the individual representation of the legs and yokes. This eliminates the use of nonexistent leakage inductances of primary and secondary windings.

The presented modeling approach can be used for predicting inrush current events and in the evaluation of the impact caused by geomagnetically induced currents (GICs).

The proposed approach is completely original and will contribute to a better understanding of the transients occurring in a transformer under abnormal conditions, such as inrush current events and GICs.

The purpose of this paper is to develop a dynamic control method to improve bus schedule adherence under connected bus system.

The authors developed a dynamic programming model that optimally schedules the bus operating speed at road sections and multiple signal timing plans at intersections to improve bus schedule adherence. First, the bus route was partitioned into three types of sections: stop, road and intersection. Then, transit agencies can control buses in real time based on all collected information; i.e. control bus operating speed on road sections and adjust the signal timing plans through signal controllers to improve the schedule adherence in connected bus environment. Finally, bus punctuality at the downstream stop and the saturation degree deviations of intersections were selected as the evaluation criteria in optimizing signal control plans and bus speeds jointly.

An illustrative case study by using a bus rapid transit line in Jinan city was performed to verify the proposed model. It revealed that based on the proposed strategy, the objective value could be reduced by 73.7%, which indicated that the punctuality was highly improved but not to incur excessive congestion for other vehicular traffic.

In this paper, the authors applied speed guidance and the adjustment of the signal control plans for multiple cycles in advance to improve the scheduled stability; furthermore, the proposed control strategy can reduce the effect on private traffics to the utmost extend.

The purpose of this paper is to propose a new simplified numerical model, based on a very compact semi-empirical formulation, able to simulate the fluid dynamics behaviors of an electrohydraulic servovalve taking into account several effects due to valve geometry (e.g. flow leakage between spool and sleeve) and operating conditions (e.g. variable supply pressure or water hammer).

The proposed model simulates the valve performance through a simplified representation, deriving from the linearized approach based on pressure and flow gains, but able to evaluate the mutual interaction between boundary conditions, pressure saturation and leak assessment. Its performance was evaluated comparing with other fluid dynamics numerical models (a detailed physics-based high-fidelity one and other simplified models available in the literature).

Although still showing some limitations attributable to its simplified formulation, the proposed model overcomes several deficiencies typical of the most common fluid dynamic models available in the literature, describing the water hammer and the nonlinear dependence of the delivery differential pressure with the spool displacement.

Although still based on a simplified formulation with reduced computational costs, the proposed model introduces a new nonlinear approach that, approximating with suitable precision the pressure-flow fluid dynamic characteristic of a servovalve, overcomes the shortcomings typical of such models.

The purpose of this paper is to investigate the applicability of a direct current (DC) hysteresis measurement on power transformer terminals for the subsequent hysteresis model parametrization in transformer grey box topology models.

Two transformer topology models with two different hysteresis models are used together with a DC hysteresis measurement via the power transformer terminals to parameterize the hysteresis models by means of an optimization. The calculated current waveform with the derived model in the transformer no-load condition is compared to the measured no-load current waveforms to validate the model.

The proposed DC hysteresis measurement via the power transformer terminals is suitable to parametrize two hysteresis models implemented in transformer topology models to calculate the no-load current waveforms.

Different approaches for the measurement and utilization of transformer terminal measurements for the hysteresis model parametrization are discussed in literature. The transformer topology models, derived with the presented approach, are able to reproduce the transformer no-load current waveform with acceptable accuracy.

In a world characterised by increasing environmental and social awareness, the number of corporate social responsibility and sustainability initiatives has significantly grown. Among these, the United Nations Global Compact (UNGC) is one of the most important, involving more than 12,000 companies. The purpose of this study is to investigate the UNGC’s worldwide diffusion, both at country and industry level, to understand the reasons leading to the highlighted dissemination patterns, and to propose various future projections.

The study pursues its objectives by applying the logistic curve model to data provided by the United Nations. The analysis is complemented by adopting instability and concentration indexes.

Results suggest that, while human rights and environmental safeguard in some areas and industries will remain a controversial issue, UNGC adoption will continue growing and giving the participants the required legitimacy to compete in worldwide markets.

To the best of the authors’ knowledge, this is the first paper that analyses the UNGC’s worldwide diffusion and proposes a prediction model for its future dissemination. The findings are of considerable importance in extending the knowledge of the initiative and in understanding the potential values of its adoption.

The number of patents in China has grown rapidly in recent years. The purpose of this paper is to investigate how patents impact economic development in China.

This paper developed an empirical model by using panel data of 42 China's patent-intensive industries to investigate the economic contribution made by Chinese patent-intensive manufacturing industries.

This paper found that the intensity of valid patents is strongly positively related to economic growth. The intensity of yearly added patents presented an inverse U-shaped and a U-shaped curve with the economy made by China’s patent-intensive industries. The correlativity mainly depended on whether the patent intensity converges near the economic indicators. Meanwhile, from the perspective of input–output efficiency, for China’s patent-intensive industries, R&D institutes were overinvested, followed by R&D intensity and R&D staff.

Investigating patent influence on economic development is quite complex research. Existing studies have mainly focused on patent protection in legal systems, but have not provided a definitive answer to what the real influence is. This study sought to narrow this gap from the patent economy perspective.

This paper illustrates how Guba and Lincoln's parallel criteria for establishing trustworthiness, can be adapted and applied to qualitative research on indigenous social protection systems. It provides insights for social protection researchers, exploring plausible qualitative research rigor evaluation criteria, on plausible alternatives.

The paper draws on qualitative evidence from a larger ethnographic study on the dynamics of indigenous social protection systems in Nigeria. It illustrates the systematic application of Guba and Lincoln's parallel criteria.

Available evidence from the study shows that Guba and Lincoln's parallel criteria is viable for establishing trustworthiness of qualitative research on indigenous social protection systems. The criteria can facilitate credible and reliable research outcomes in research on improving social protection policy and practice.

Qualitative inquiries that draw on Guba and Lincoln's parallel criteria as evaluation criteria for trustworthiness can complement quantitative research on social protection. This makes it imperative to incorporate both, in social protection research for a holistic system. How this can be done is beyond the scope of this paper but needs to be explored by future research.

Contrary to the use of Guba and Lincoln's parallel criteria in qualitative research in other contexts, the use of the criteria has not been carefully examined in qualitative research on indigenous social protection systems. This paper is an attempt to fill this gap.

This paper investigates how sustainability requirements modify supply strategies at different levels in the food industry companies. The paper integrates single supply decisions into firm-level supply strategy and views supply strategy as one coherent strategy in which the decision-making is based on the values and principles of a firm.

The paper captures the decade of change and studies the renewal of supply strategy by utilising two qualitative data sets with a ten years of difference. The data contain 41 interviews from a retailer and 5 of its food supplier companies.

Results confirm that a decade ago only minor attention was channelled towards sustainability whereas today sustainability is a key driver behind supply decisions and supply strategies because firms need to respond to sustainability requirements and challenges. The study presents a framework for analysing different levels (firm, category and supply market levels) of changes and sustainability requirements faced by food companies and their supply strategies.

Previously, sustainability has rarely been connected to firm-level supply strategy. This study presents the supply strategy elements that were important for Finnish food industry companies over a decade ago and matches these elements to the needs of today’s firms. As a result, the study incorporates the concept of sustainability with the supply strategy frameworks.

This work aims to analyze the university–industry interaction in innovation ecosystems. The problem under study addresses how agents can operate in university–industry interactions to enhance the connections, specifically in the aspect of operational mechanisms of an innovation ecosystem.

The study is qualitative, applied through grounded theory approach, cross-sectional and multiple sources of evidence – semi-structured interviews were conducted. An explanatory conceptual model was subsequently compared with the literature and validated with specialists.

The results showed that the university–industry interaction is influenced by several factors, such as networking, legal support, facilitating agents, management practices. Despite this, some other factors were identified for the improvement of U–I relationships, such as: strengthening of triple helix, greater legal certainty and encouragement of open innovation.

The small sample size and the heterogeneity among the universities interviewed did not allow full saturation to occur. In spite of that, a significant level of saturation with respect to the challenges and barriers was observed.

This work has a direct dialogue with researchers, managers and actors involved in university–industry interaction with regard to increasing the capacity for creation and dissemination of knowledge among organizations, educational institutions, government and companies.

By adopting a grounded theory approach, a detailed research agenda addresses research needs in two main areas: activities that precede the interaction between universities and companies, and the organization and management of the consequences of collaborative relationships.

This study aims to describe and evaluate various visual and creative tools for supporting the in-depth biographical interview aimed at analyzing educational communities and their stakeholders.

Researching educational spaces today requires new ways of understanding, analyzing and studying. The complex characteristics, functions and realities demand research that responds to educational singularities. It is a matter of deeply understanding the educational phenomenon's peculiarities. For these purposes, instruments and research paradigms are needed to extract data and reach information saturation regarding the data obtained from the proposed objects of study. With this in mind, the following paper suggests reflecting on data collection tools that can complement the interview and biographical-narrative research approach. The authors highlight the use of photo-elucidation, the biogram-based timeline, the organigram and the flight of the geese, all of which are instruments endowed with a visual character that allows a deeper understanding of the object studied.

The main contribution of this paper is to unpack the uses and applications of four visual tools that support the interview technique. First, photo-elucidation is presented as a sensory strategy to stimulate the narrative during the dialogical exchange of the interview. Next, the timeline is described as a visual concretization of the traditional biogram widely used in educational research. Next, the authors unravel the uses of the organizational chart in educational research, which, due to its nature and utility, provides a glimpse of the organizational functioning of an institution and is particularly suitable for research in institutional frameworks. Finally, the tool known as the flight of the geese is presented. This tool is recommended for use in educational leadership and teamwork studies due to its simplicity and high representativeness of the hierarchy of roles and functions.

Researching educational spaces today requires new ways of understanding, analyzing and studying. The complex characteristics, functions, and realities demand research that responds to educational singularities. It is a matter of deeply understanding the educational phenomenon's peculiarities. For these purposes, instruments and research paradigms are needed to extract data and reach information saturation regarding the data obtained from the proposed objects of study. With this in mind, the following paper invites us to reflect on data collection tools that can complement the interview and biographical-narrative research approach. The authors highlight the use of photo-elucidation, the biogram-based timeline, the organigram, and the flight of the geese, all of which are instruments endowed with a visual character that allows a deeper understanding of the object studied.