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The electrical machines connected to modern electric power grids are non-sinusoidal excited, and their augmented losses, including iron losses, limit their working characteristics. This paper aims to propose a prediction method for iron losses in non-oriented grains (NO) FeSi sheets under non-sinusoidal voltage, involving an inverse classical Preisach hysteresis model and the time-integration of each loss component.

The magnetic history management in inverse Preisach model is optimized and a numerical Everett function is identified from measured symmetrical hysteresis cycles. The experimental data for sinusoidal waveforms obtained by a single sheet tester were also used to identify the parameters involved in Bertotti’ losses separation method. The non-sinusoidal magnetic induction waveform, corresponding to a measured voltage in an industrial electrical grid, was the input for Preisach model, the output magnetic field being accurately computed. The hysteresis, classical and excess losses are calculated by time-integration and the total losses are compared with those obtained for sinusoidal excitation.

The proposed method allows to estimate the iron losses for non-sinusoidal magnetic induction, using carefully identified parameters of FeSi NO sheets, using experimental data from sinusoidal regimes.

The method accuracy is assured by using a numerical Everett function, a variable Preisach grid step (adapted for the high non-linearity of FeSi sheets) and high-order fitting polynomials for the microscopic parameters involved in the excess loss estimation. The procedure allows a better design of magnetic cores and an improved estimation of the electric machine derating for non-sinusoidal voltages.

This study examined dossiers of informative pursual (DIPs), a particular type of secret police files, before and after the fall of Communism in Romania. These DIPs were often weaponized against citizens perceived to be anti-government.

Based on Buckland's (2017) concept of a document as an object with physical, mental and social parts, the study used thematic analysis to examine volumes of DIPs from 1945 to 1989 Communist Romania as well as several recorded reactions to the DIPs by the victims who were targeted by the Communist secret police.

Four themes were revealed by the study's findings and discussed within the manuscript: DIPs as unreliable epistemic tools, DIPs as tools to construct the identity of the “People's Enemy,” DIPs as weapons to fight the “People's Enemy” and DIPs as tools that could be used in counterattacks during post-Communism, including in political-economic blackmailing.

There are two major limitations to research of DIPs. First, since many DIPs have been stolen, copied illicitly or even destroyed, it is difficult to articulate precisely their actual or potential social and political effects. Researchers may often detect these effects only indirectly, based on information leaks in the news. Second, many victims of surveillance practices during the Communist period have chosen not to leave records of their reactions to reading the DIPs that targeted them.

Current and future comprehensive studies of DIPs can reveal possible parallels between surveillance by the Communist regime and the massive data-collection that occurs in democratic societies, particularly given the increased technical capabilities for processing data in these democratic societies.

Within documentation studies, secret police files and document weaponization have been particularly under-researched, therefore this study contributes to a small body of literature.

This paper aims to identify campus greening initiatives on a sample of universities in Romania reflected in the university curricula, the behavioral patterns of students and teachers, the administrative actions that carry out empirical investigation of students/teachers/management staff perception on campus greening (based on self-administered questionnaires); detect the way campus greening initiatives are promoted/made visible; and identify the gaps and needs of the universities under scrutiny in terms of campus greening initiatives.

The current research relies on two major components reviewing campus greening-related activities and initiatives, as reflected in the scientific literature and university curricula (empirical and quantitative assessment) and inquiring selected universities’ about the campus greening programs they unfold through questionnaire surveys (qualitative assessment).

Generally, sustainability topics (e.g. environmental protection, waste management and sustainable development) are largely addressed and, to some extent, applied in faculties dealing with earth sciences (e.g. geography, ecology) and technical sciences (e.g. environmental engineering). This can be explained by the traditional theoretical background of the first, and the experimental-oriented profile of the latter, which supports the development of innovative technologies (green technologies). However, there is a need to better undertake and promote greening initiatives for most of the higher education institutions in Romania. Some spatial (between institutions throughout Romania) and structural (according to the profile of the institutions) disparities are visible.

The limitations of the study might be the small number of universities providing a positive feedback to the questionnaire survey and the degree of subjectivity of some of the answers, directly linked with the professional background and issue awareness of the persons who answered the questions.

The findings can be useful to the university managers to better orient their actions toward campus greening, increasing their knowledge and awareness toward sustainability-related actions.

This is the first attempt reporting in the literature to analyze the campus greening initiatives to a large number of universities in Romania based on a common approach, identifying the main gaps and challenges in this process.