bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Assessment of PID and ANFIS Controllers in an Automatic Voltage Regulator
Authors: Ghimire Sajesan , Bhattrai Bhriguraj , Shrestha Sulav , Poudel Sagar
Published: February 2025

This research paper provides an in-depth analysis of the performance characteristics of PID (Proportional-Integral-Derivative) and ANFIS (Adaptive Neuro-Fuzzy Inference System) controllers within Automatic Voltage Regulator (AVR) systems. The primary objective is to evaluate these controllers' behavior and efficacy, potentially extending their application to other control systems in the power sector. Utilizing the robust capabilities of MATLAB-SIMULINK, the PID controller was finely tuned, while the ANFIS controller was trained using carefully selected data. The findings highlight the ANFIS controller's exceptional performance, characterized by a notably fast settling time of 1.7277 seconds and 1.8716% overshoot. In comparison, the PID controller exhibited greater overshoot and a longer settling time, demonstrating less efficiency. These results were compared with other published research papers, further validating the superior performance of the ANFIS controller. This detailed evaluation confirms the ANFIS controller's superiority, offering significant guidance for researchers and industry professionals in making informed decisions regarding the optimal choice of controllers for various control systems.
Diversity of teaching methods is the main didactic principle in planning and developing training sessions in higher education institutions
Authors: Gadzaova Liudmila Petrovna
Published: February 2025

In the chapter examines the current problems of teaching and learning a foreign language. The author will raise questions not so much of a theoretical nature, but how to solve them. The paper attempts to show how, when planning and designing a lesson, to focus on practical points dictated and recommended by didactic and pedagogical theory. The author considers the methodological organization of teaching a foreign language in a regional university, the reaction to the problems of traditional and digital teaching and learning, set out as consistent theoretical foundations before specific methodological recommendations. The research is aimed at supporting all teachers who want to purposefully and quickly prepare for the methodological planning, development and conduct of classes.
DISCHARGES IN CONTACT WITH LIQUIDS: ELECTRICAL CHARACTERIZATION OF A PULSED CORONA DISCHARGE
Authors:   Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto,(UTN) Laprida 651 – (2600) Venado Tuerto – Prov. Santa Fe – Argentina., Milardovich N. , Ferreyra M. ,   Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto,(UTN) Laprida 651 – (2600) Venado Tuerto – Prov. Santa Fe – Argentina., Chamorro J.C. ,   Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto,(UTN) Laprida 651 – (2600) Venado Tuerto – Prov. Santa Fe – Argentina., Prevosto L. ,   Universidad Tecnológica Nacional, CONICET, Facultad Regional Venado Tuerto Departamento Ing. Electromecánica,Grupo de Descargas Eléctricas Laprida 651 (2600) – Venado Tuerto – Prov. Santa Fe – Argentina.
Published: February 2025

The large number of works published in recent years on non-thermal discharges in (and in contact with) liquids, shows the growing interest in this particular field of electric discharges due to the large number of technological applications.In particular, one of the fastest growing emerging applications is the treatment of water, both for its purification andfor its activation, with a view to carrying out the indirect treatment of food and seeds with non-thermal discharges; without the addition of chemicals. In this work, the experimental characterization of a corona discharge in contact with water operating in a pulsed regime is presented. A flat-wire type geometry was used with the flat electrode immersed in water. The discharge was powered through a pulsed capacitive type source, capable of providing a periodic train ofhigh voltage pulses (∼15 kV) with short duration (∼100 ns), with a repetition frequency of 40 pulses/s. The results of discharge voltage and current measurements are reported and discussed for different operating conditions, and the instantaneous power and energy dissipated in the generated plasma are inferred. Photographs in the visible with long exposure times of the pulsed discharge are also shown.
The Cloud Computing and Performance: Systematic Literature Review (by PRISMA Method)
Authors: ELHALOUMI Redouane , JABRAOUI Siham
Published: February 2025

Objectives: The study examines the impact of cloud computing adoption on business performance. The study aimed to analyze and classify the contributions of the studies published in the cloud computing field. The cloud literature is analyzed systematically from the management and business points of view. The review is limited to journal articles and papers published between 2013 and 2024. Methods: Based on the PRISMA methodological guide, mixed quantitative and qualitative methods were used. Results: The study concluded that there is an effect of cloud computing adoption on performance in the sample of articles studied and that there is a positive relationship between most dimensions of cloud computing adoption by SMEs and performance dimensions. Conclusions: The study recommended the necessity of paying attention to Cloud computing technology because of its effective role on performance first and then completing work with the required efficiency and effectiveness.
From Detection to Recovery: How Artificial Intelligence is Changing the Landscape of Oral Cancer Management
Authors: Pandey Ashish
Published: February 2025

Oral cancer is a significant global health challenge, with rising incidences and high mortality rates, particularly in the late stages. Early detection and effective management are crucial for improving patient outcomes. Artificial intelligence (AI) is rapidly transforming oral cancer management by enhancing early detection, improving treatment planning, optimizing post-operative care, and supporting rehabilitation. This article explores the integration of AI into various stages of oral cancer management, including diagnosis, surgical treatment, post-operative care, and rehabilitation. It also addresses the ethical and regulatory challenges associated with the adoption of AI technologies in clinical practice, providing a comprehensive review of the current state and future prospects in this field.
Procedures for the Handling of Contaminated Armament Related Sites
Authors: Dahn André
Published: February 2025

The investigations were performed on sites contaminated with explosives and their related metabolites. My presentation consists of the following chapters. Firstly, I give some information about the Situation in Germany as regards explosive contaminated sites. Further, I describe the processing phases for the site investigation, in brief and then examining some examples of processes for historic inquiry, orientation and detailed investigation and a remedial investigation. The last mentioned was funded as a project by the Federal Ministry for Education and Research – Investigation on Remediation of Explosive Contaminated soil, including the testing of large scale remediation methods. Finally I give some information in brief about a project where natural attenuation processes in explosive contaminated sites were investigated, and some results in the summary. Before starting my presentation, I give a brief description of our firm's credentials in the field.
Preventive Measures are the best Disaster control – the Checklist method
Authors: Platkowski Jurg
Published: February 2025

Preventive measures are the best disaster control. For this reason the principal aim of the project “Technology Transfer for Plant-related Water Protection in Moldavia, Romania and the Ukraine” was the development of a simple and clearly structured method for water analysis, with regard to the safety of ground and surface water, which is adaptable to the economic and technological capabilities in the participating countries. Based on international recommendations, e.g. the Joint River Bodies, we elaborated the so called Checklist Method.
Results of a performed course of pectin-prophylaxis in preschool children of an industrial city
Authors: Biletska Eleonora M.  , Glavatska V.I.
Published: February 2025

This manuscript is devoted to the study of regional peculiarities of lead prevalence in the environment of industrial regions of the city, in dynamics and the ascertainment of its complex impact on donosologic findings of the health of preschool children. In this work the dependence between changes in the health of children, living in an ecologically unfavourable region and the lead content in the environment and in the human system is investigated. It is determined that despite relatively low concentrations of lead in the objects of the environment, in the children's bodies, this abiotic metal is determined in increased concentrations and negatively impacts on immunological, biochemical, psychophysiological data and micro element status of preschool children. This leads to decreased levels of the substances that have a protective action and limit absorption of lead. The necessity of performing individual bioprophylaxis in children subjected to lead impact is substantiated. The data proves the efficacy of using pectin food additives as a means of improving children's health.
Seismotectonic Conditions and Seismic Risk for Cities in Georgia
Authors: Varazanashvili Otar  , Tsereteli Nino  , Muchadze Teimuraz
Published: February 2025

At 22:41 local time, on Tuesday, April 25, 2002, a moderate earthquake with magnitude M = 4.6 took place in the Tbilisi area. This was the strongest instrumentally recorded seismic event ever in this region, causing 7 deaths, making 2446 people homeless and causing 180 million US$ worth of damage. The Tbilisi earthquake was a strike-slip earthquake that took place on the NW-SE Tbilsi-Mtkvari fault that dips to the northeast. The focal mechanism and shape of the isoseismals confirm this. A year before the Tbilisi earthquake of 2002 a seismic risk was evaluated for the town. In particular, the distribution of social-economic damage in the territory of the town in case of single earthquakes with intensities 7 and 8, i.e. so called “scenario” earthquakes, was determined. Obtained schematic map of the direct economic loss on the territory of the town gives the distribution of the relative seismic risk in the territory of the town and shows well the most vulnerable parts of the town in case of an earthquake with intensity 7. Calculated for them, potential direct economic loss is of the same order as that received by risk calculations according to official data after the Tbilisi earthquake of 2002 (April 25). For comparison, according to calculations in case of an earthquake with intensity 8 direct economic loss from destruction and damage of buildings only could exceed milliard dollars in the territory of Tbilisi. At 11:44 local time, February 20, 1920, a strong earthquake with magnitude Ms = 6.2 took place in the Gori area. The seismic intensity of this earthquake was estimated as IIX on the MSK scale in Gori. Half of the thousand apartment houses in the town were ruined and others were damaged. This event caused 114 deaths in the Gori area, half of them in the town of Gori. Perspective development of Gori requires the estimation of seismic risk for this territory. Existing data makes it possible to estimate the levels of economic loss caused directly by damaged and ruined buildings that in turn would be generated by earthquakes of various intensities. Particularly, the seismic risk for Gori has been estimated for scenario earthquakes with intensity 7, 8 and 9. Estimated value of losses for earthquakes with intensity 7. 8 and 9 are 60, 170 and 300 million US dollars respectively. The direct economic loss to Gori, caused by the Qartli earthquake of 1920, is estimated (at current prices) at 30 million US dollars. The maps of seismic risk for Gori give a visual demonstration of the most damaged areas. Hence, it is of great importance to establish a system of preventive practical measures which will make it possible to decrease the destructive effect of earthquakes in Tbilisi and Gori. Results of distribution of quantitative values of potential detriment to the cities' territories, which are received on the basis of seismic risk assessment, create necessary prerequisites for solving this problem.
Main foundations of ecological safety of environment and residents in an area influenced by tailing deposits of radioactive waste
Authors: Anishchenko Ol'ga
Published: February 2025

The purpose of this research is the estimation and forecasting of the level of environmental contamination for the elaboration of a local system of geoecological environment monitoring in an area influenced by the storage of radioactive waste products. As result, the main foundations for the ecological safety of the environment and inhabitants in an area influenced by tailing deposits of radioactive waste from the uranium-mining industry and the uranium-concentrating industry have been formulated.
Acculturation Patterns and Adaptation of Immigrants in Greece
Authors: Besevegis Elias  , Pavlopoulos Vassilis
Published: February 2025

The purpose of the present study was to explore the acculturation patterns of immigrants in Greece in relation to their economic and psychological adaptation. The following research questions were examined: How do immigrants adapt to the host culture? How do they deal with the multiple pressures and challenges of “culture shock”? What is the relationship between acculturation strategies and the quality of adjustment? The sample consisted of 601 immigrants (43% women) from 35 nationalities who resided in urban and rural areas in the host country (mean length of stay: 8 years). Results indicated that levels of adaptation varied according to the cultural distance hypothesis, with immigrants from Europe and the Balkans doing better than immigrants from sub-Sahara African and Islamic countries. Most immigrants chose to integrate (46%); 21% assimilated; 25% were separated; and 8% reported an individualistic profile. Acculturation strategies were related to the quality of adaptation, i.e. integration and assimilation yielded the most positive outcomes and separation the most negative. Length of stay in the host country had an indirect effect on adaptation through the acculturation variables. Implications of findings for policy making are discussed.
On a Family of Perfect Nonlinear Binomials
Authors: Helleseth Tor  , Kyureghyan Gohar  , Ness Geir Jarle  , Pott Alexander
Published: February 2025

A mapping f: GF(pn)→GF(pn) is called differentially k-uniform if k is the maximum number of solutions x∈GF(pn) of f(x+a)−f(x)=b, where a,b∈GF(pn) and a≠0. A 1-uniform mapping is called perfect nonlinear (PN). In this paper we discuss some problems related to the equivalence of perfect nonlinear functions, and describe a class of perfect nonlinear binomials ux+x2in GF(p2k). These are the first PN binomials known to us which are composed with inequivalent monomials. We show that this family of binomials is equivalent to the monomial x2. We survey some of the close connections between perfect nonlinear functions and finite affine planes, in particular those which are important for equivalence proofs.
Classification of Boolean Quartic Forms in Eight Variables
Authors: Langevin Philippe  , Leander Gregor
Published: February 2025

We present the strategy that we recently used to compute the complete classification of Boolean quartic forms in eight variables. Furthermore, we outline some applications of this result.
Local Affinity of Boolean Mappings
Authors: Logachev Oleg A.  , Yashchenko Valery V.  , Denisenko Mikhail P.
Published: February 2025

We introduce new concepts and parameters related to the problem of studying the behavior of a Boolean mapping on flats. We also prove several results relating these concepts and parameters with cryptographic properties of Boolean mappings. Moreover, the paper contains many examples.
Decimation Based Algebraic and Correlation Attacks and Design of Boolean Functions
Authors: Mihaljević Miodrag J.
Published: February 2025

Security evaluation techniques relevant for some models of stream ciphers based on linear feedback shift registers and Boolean functions are addressed. The article points out to some recently developed advanced algebraic and correlation attacks and their implications regarding design of secure Boolean functions. The considered cryptanalytic approaches are based on appropriately decimated sample resulting into conversion of certain Boolean functions into the weaker ones.
On the Nonexistence of Homogeneous Rotation Symmetric Bent Boolean Functions of Degree Greater Than Two
Authors: Stănică Pantelimon
Published: February 2025

In this paper we present a result towards the conjectured nonexistence of homogeneous rotation symmetric bent functions having degree >2.
On Algebraic Algorithms Deciding Properties of Discrete Functions
Authors: Alekseev Valeriy
Published: February 2025

In this paper we introduce the notion of logical semiring and give examples of using such semirings in designing fast algorithms for discrete problems.
Tight Bounds between Algebraic Immunity and Nonlinearities of High Orders
Authors: Lobanov Mikhail
Published: February 2025

Among cryptographically significant characteristics of Boolean functions used in symmetric ciphers the algebraic immunity and the nonlinearities of high orders play the important role. Some bounds on the nonlinearities of high orders of Boolean functions via its algebraic immunity were obtained in recent papers. In this paper we improve these results and obtain new tight bounds. We prove new universal tight lower bound that reduces the problem of an estimation of high order nonlinearities to the problem of the finding of dimensions of some linear spaces of Boolean functions. As simple consequences we obtain all previously known bounds in this field. For polynomials with disjoint terms we reduce the finding of dimensions of linear spaces of Boolean functions mentioned above to a simple combinatorial analysis. Finally, we prove the tight lower bound on the nonlinearity of the second order via its algebraic immunity.
Hotwiring the Apocalypse: Apocalyptic Elements of Global Jihadi Doctrines
Authors: Paz Reuven
Published: February 2025

Various Islamic groups see recent events as presaging an ‘apocalypse’ that will see the destruction of the West. Some of these groups believe they can ‘hotwire’ this, i.e. bring it about through the use of WMD in anti-Western attacks. However, their ability to do so is doubtful.
Mad, Bad or Freedom Fighters: The New Challenges of Terrorism
Authors: Taylor Max
Published: February 2025

The ‘new’ terrorism differs from the ‘old’ in important ways, but they are ultimately similar. The best counter to terrorism in the long-term is likely to be the growth of civil society, which is best pursued by non-military means.
Suicide Bombing: a Possibility for France?
Authors: Géré François
Published: February 2025

So far there have been no instances of suicide bombing on French soil. Does this mean that for some obscure reason France has been spared? Is it a sanctuary protected by some covert governmental leniency towards terrorist organizations? Or is this due to French refusal to participate in military operations in Iraq? A short review of the past and the present situation demonstrates that France has been and still remains a major target which has to be protected from the kind of attack suffered in both Spain and the United Kingdom. The current situation must be attributed to an accurate assessment of the adversary, persistent effort by the security forces (police, gendarmerie, DGSE) and, so far, a jolly good piece of luck.
Suicide Prevention Among Polish Veterans of Multinational Missions
Authors: Ilnicki Stanislaw
Published: February 2025

This paper presents some outcomes of the participation of Polish Military Contingents (PMC) in multinational missions and military operations within the UN, OSCE, EU and NATO mandate. The suicide risk among soldiers serving both in country and abroad is discussed. Selected legal issues and organization of the combat stress disorders prevention system in the Polish armed forces were presented. In particular, prevention activity before deployment, during deployment and after returning home was highlighted. Achievements and challenges in PTSD prevention and treatment in the PMC were discussed.
Pharmacotherapy of Suicidal PTSD Patients
Authors: Henigsberg Neven  , Kovacic Zrnka  , Kalember Petra
Published: February 2025

The rate of co-morbidity is very high in posttraumatic stress disorder (PTSD) especially major depressive disorder and substance abuse. It is not clear if the suicidality in PTSD patients is predominantly caused by core PTSD symptoms or by co-morbid disorders. There is a lack of randomized controlled trials for treatment of suicidality in PTSD. Selective serotonin reuptake inhibitors (SSRIs) are widely used in PTSD treatment, but there is some evidence that they can increase risk of suicidality (self-harm behavior, suicidal thoughts, and suicide attempts) in younger age groups. Benzodiazepines have not been proven effective in the treatment of PTSD core symptoms. Benzodiazepines can even worsen clinical symptoms after acute traumatic experience, and they can induce consequent PTSD and depression, which may lead to increased suicidal risk.
Stress Events in a Month Before Suicide, Aggression and Impulsivity of Suicide Victims Relevant for Military Population
Authors: Pregelj Peter  , Tomori Martina  , Dolničar Robert  , Balažic Jože  , Zupanc Tomaž
Published: February 2025

Although military personnel are trained for combat and peacekeeping operations, accumulating evidence indicates that deployment-related exposure to stress events is associated with mental health problems and suicidal behaviour. Suicide accounted for substantial mortality among army personal and veterans. This data could be partially explained with observation that war-zone exposures may have considerable negative emotional or behaviour consequences. On the other hand, it is also well known that some personal characteristics as impulsivity and aggression could be connected with higher suicide risk. The extent to which violent and aggressive behaviour in the aftermath of deployment can be attributed to combat experience remains an area of debate and ongoing investigation. The aim of our study was to evaluate negative life events of suicide victims in a month before suicide. On the other hand, aggression and impulsivity of suicide victims was evaluated. In the three-year period, 90 suicide victims (28 women and 62 men) in the central region of Slovenia were examined using the method of psychological autopsy performed by specially designed questionnaire and from medical documentation. We compared a subgroup of suicide victims with previous aggressive behaviour and a subgroup of suicide victims without any previous reported aggressive behaviour. We observed that suicide victims with previous aggressive behaviour have higher a number of negative life events in the month before suicide and have higher impulsivity then others. We also observed that suicide victims with previous aggressive behaviour directed toward others have more often previous suicide attempts than suicide victims without previous aggressive behaviour. It could be concluded that negative life events of suicide victims with previous experience of aggressive behaviour may additionally contribute to increased suicide risk. In military environments, attention should be paid to such vulnerable individuals, especially during pre-deployment periods.
Virtual Reality as an Adjunct for Training and Treatment
Authors: Wiederhold Brenda K.  , Wiederhold Mark D.
Published: February 2025

For more than a decade, virtual reality (VR) has had a significant impact on behavioral healthcare, permeating the field with its multiple effective uses. One area in which VR shines is providing a continuum of care for the military to treat wounded warfighters. The Interactive Media Institute and its affiliate the Virtual Reality Medical Center are funded to provide VR as an adjunct to traditional training and therapeutic applications.
A Review of the U.S. Army Soldier Suicides in Iraq
Authors: Castro Carl A.  , Mcgurk Dennis  , Wright Kathleen M.
Published: February 2025

The Mental Health Advisory Team (MHAT) IV was established by the Office of the U.S. Army Surgeon General at the request of the Commanding General, Multi-National Force-Iraq (MNF-I). The mission of MHAT IV was to (a) assess Soldier and Marine mental health and wellbeing, (b) examine the delivery of behavioral health care in Operation Iraqi Freedom (OIF), and (c) provide recommendations for sustainment and improvement to command. Part of the MHAT IV mission was to review the status of the theater's suicide prevention and surveillance programs, including an analysis of completed suicides. The MHAT IV assessed the mental health of the deployed force from August 28, 2006 to October 3, 2006. Recommendations are based on findings from anonymous Soldier (N = 1,320) and Marine (N = 447) surveys, and on behavioral health, primary care, and unit ministry team surveys; focus group interviews with Soldiers and Marines, as well as interviews and focus groups with Army and Navy behavioral health personnel; various secondary sources; and personal observations by team members.
Lowering Suicide Risk: Situation and Prevention Measures in the Lithuanian Armed Forces
Authors: Lapenaite Danute  , Vaicaitiene Ramute
Published: February 2025

In spite of the fact that the suicide rate in Lithuania decreased during the past years, it is still one of the highest in Europe. 1 to 1.5 thousand people commit suicide in Lithuania every year. In 2006, the suicide rate was 30.9 per 100,000 people. Men commit 84% of all suicides. The number of male suicides is six times higher than that of female suicides. Men of average age living in rural areas have the highest risk of suicide. The ratio of attempted suicides to committed suicides is 10:1. Official data on suicide in the Lithuanian Armed Forces has existed since 1993. There have been few suicide cases in the Lithuanian Armed Forces since then. The amount of suicides are spread nearly equally among conscripts, officers, and non-commissioned officers. The suicide rate ranged from 0.15 to 0.34 per 1,000 servicemen for several years. Since 2004, the rate remains more or less level and does not exceed 0.2 per 1,000 servicemen. There is a need for suicide prevention measures, both in the country and in the Armed Forces, in spite of the fact that suicide rates in the military are not as high as in the civilian population. Suicide prevention measures should be applied not only to conscripts but to military professionals as well as officers and non-commissioned officers who are deployed. Scientific research findings [1] have shown an above average prevalence of suicidal behavior among servicemen, a low level of knowledge about suicide, inappropriate attitudes toward suicide, and a positive view on suicide prevention in the military, which became the background for the Program of Psychological support in the Lithuanian Armed Forces. The Program, with a wide spectrum of prevention measures, include: training, education, psychological support for servicemen and their families, additional care of personnel with psychological problems, and/or the risk of suicide, and monitoring of servicemen's psychological wellbeing, is in progress. The efficiency of this program is now being assessed. Since 2006, incident handling for service personnel by psychological support professionals has been organized not only in Lithuania but in the mission area as well. The concept of psychological support for service personnel and their families across the deployment cycle was validated and is now being successfully implemented.
The Turkish Counter-Terrorism Experience
Authors: Özeren Suleyman
Published: February 2025

This chapter describes the key terrorists threats to Turkey and the main features of the country's institutional response to these challenges. Four types of terrorism threaten Turkey: left-wing groups, right-wing groups, separatist movements, and Al-Qaeda connected international terrorism. Turkey's Interior Ministry is the key agency responding to these threats. The authorities have carried out successful operations through diplomacy and working to address the root causes of terrorism. Nevertheless, Turkey does not always receive the attention it deserves from the international community. Much more work is needed in building an international coalition and addressing terrorism's underlying causes. Turkey could make a much larger contribution to international counter-terrorism efforts by training other law enforcement agencies.
Psychology of Terrorists and Profile of Suicide Bombers
Authors: Eren Seyit Ahmet
Published: February 2025

The lecture begins by evoking the thought world of the terrorist, dominated by notions heroism and evil. The importance of the ideology is emphasized. Focusing on suicide bombers, the lecture provides ‘in broad terms’ the profile of an attacker. The motivations of the suicide are listed, as are the demands placed on him/her by the terrorist group. This chapter also answers the question why women are preferred as suicide attackers. In conclusion, it notes that “not only the security forces but all other institutions and civil society must get involved in coping with suicide terrorism”.
Terrorism and Organized Crime
Authors: Freeman Michael
Published: February 2025

The nexus of organized crime and terrorism is complex and an increasingly important issue for policy makers. Frequently, terrorist groups and organized crime look much alike structurally and engage in similar activities, yet there are also some crucial differences in their acceptance of risk, their motivating ideology, and their use of violence, for example. Furthermore, terrorist and criminal groups often work together and these alliances have a force multiplying effect in terms of the dangers they might pose to the state.
Numerical Methods for Calculation of Eddy Current Losses in Permanent Magnets of Synchronous Machines
Authors: Petrovic Lj.  , Binder A.  , Deak Cs.  , Irimie D.  , Reichert K.  , Purcarea C.
Published: February 2025

Eddy current losses in rotor permanent magnets (PM) of synchronous machines are calculated for sinusoidal stator currents and for PWM inverter supply. Three calculation methods are compared in the FE environment: a) time-stepping method, b) quasi-static method, c) semi-analytical post-processing. These 2D methods are with end effect coefficients, and they consider the time variation of currents and of the rotor position. Whereas method a) includes the variation of flux-density over the magnet cross section and the reaction field of the eddy currents, method b) is neglecting the reaction field. Method c) in several variants features either neglecting of the eddy current reaction field or an averaging of the flux density along the magnet width or height. Neglecting the reaction field is possible for materials with low conductivity and low permeability like rare-earth magnets for low to medium frequencies up to several kHz. The quasi-static methods need less computation time, but depend on the machine geometry like stator MMF wave length, slot pitch, segmented vs. massive magnets and small or big magnet height. The comparison of methods a), b), c) is given for two different stator geometries of permanent magnet synchronous machines with open vs. semi-closed slots and surface-mounted vs. buried magnets.
Coordination of Surge Protective Devices Using “Spice” Student Version
Authors: Sartori Carlos Antonio França  , de Oliveira Otávio Luís  , Cardoso José Roberto
Published: February 2025

This paper presents a methodology concerning Surge Protective Device (SPD) Coordination Studies; taking into account the available tools of the student version of the “Spice”. As an approach to satisfy the related limitations of this version, preliminary analytical studies are carried out; allowing us to selected a list of the available Spice SPD models to be applied in the simulations. Some applications regarding residential installations were chosen, and their results are presented and compared with the ones presented in literature.
Radiation in Modeling of Induction Heating Systems
Authors: Barglik Jerzy  , Czerwiński Michał  , Hering Mieczysław  , Wesołowski Marcin
Published: February 2025

The paper presents analysis of third type boundary conditions applied for numerical simulation in more frequently used induction heating systems. A special emphasis was put on analysis on radiation heat transfer with taking into consideration multiple reflections phenomenon. Obtained results confirmed necessity of usage of multiple reflections model for analysis of high temperature induction heating systems.
Applicability of Microwave Frequencies to the Evaluation of Deeper Defects in Metals
Authors: Faktorová Dagmar
Published: February 2025

The paper deals with non-destructive (NDT) microwave measurement of defects in metal samples exploiting the waveguide features at the defect depth evaluation. In this article some results concerning their evaluations regarding to microwave access are shown. More measurements were performed to evaluate the geometry of defects in metal samples. Apart from established methods two new unusual microwave connections are presented and the results with their use at defects examination are given and compared with the previous results. Their advantages are discussed and some proposals for their utilizations are given.
Time-Domain Analysis of Self-Complementary and Interleaved Log-Periodic Antennas
Authors: Lalas A.X.  , Kantartzis N.V.  , Tsiboukis T.D.
Published: February 2025

A systematic near- and far-field analysis of dual polarisation log-periodic antennas is presented in this paper. The investigation of these demanding structures is performed by means of a 3D finite-difference time-domain (FDTD) methodology, properly tailored to tackle their geometrical details and abrupt discontinuities. In particular, the analysis delves into the design parameters of self-complementary, interleaved and trapezoidal-toothed structures and conducts a thorough examination of their radiation characteristics. Furthermore a new discretisation concept involving very flat cells which enhance algorithmic performance is introduced. Numerical verification addresses an extensive set of realistic applications with diverse parameter setups as well as instructive comparisons which indicate the merits of the proposed formulation.
FEM Study of the Rotor Slot Design Influences on the Induction Machine Characteristics
Authors: Kappatou Joya  , Gyftakis Kostas  , Safacas Athanasios
Published: February 2025

A library of parameterized Squirrel Cage Induction Machine models has been constructed regarding the rotor slot design and is used to investigate the influences of the rotor bars shape on the machine characteristics. The slot shapes chosen correspond to standard induction machines used for specific applications. The calculations were conducted using the Finite Element Model (FEM) of the machine and the torque and current waveforms against speed, as well as the field distribution and the copper losses in the rotor bars for every model at starting have been obtained. Useful conclusions about the influences of the slot design on the Induction Machine behavior, mainly at starting are derived.
Concentrated Wound Permanent Magnet Motors with Different Pole Pair Numbers
Authors: Salminen Pia  , Jussila Hanne  , Niemelä Markku  , Pyrhönen Juha
Published: February 2025

The study addresses the torque production capabilities and losses of concentrated wound permanent magnet machines. Different permanent magnet synchronous motors are modelled with both semi-closed slots and open slots. With open slots, the coils can be easily assembled to the stator, thus making it attractive to study the performance or benefits of the concentrated wound PM machines with open slots. Different slot and pole combinations are considered on the basis of the finite element analysis (the Flux2D program package by Cedrat being employed in the computations).
Electromagnetic Field Energy in Ferromagnetic Barriers
Authors: Niedbała Ryszard  , Kucharski Daniel  , Wesołowski Marcin
Published: February 2025

This paper refers to electromagnetic field propagation around high-current circuits. The effects of its influence on conducting bodies that are seals and casings of electric devices are discussed. These barriers which are the constructional parts are made of ferromagnetic materials – good absorbers of energy transformed into heat in their structures. Intensity of absorbance depends on the distance between the barrier and source of radiant energy. Limitation of diffusing energy by absorbing it requires a high accuracy quantitative analysis to assure a high value of absorption coefficient and optimal power density of heat sources. The analysis results of basic geometries are shown.
Squirrel-Cage Induction Motor with Intercalated Rotor Slots of Different Geometries
Authors: Fireţeanu V.
Published: February 2025

This paper deals with a particular design of squirrel-cage rotor slots and copper bars of high power induction motors able to ensure high values of both starting torque and breakdown torque. The innovation consists in a rotor with two different geometries of slots, respectively of bars cross-section shape. Along the rotor periphery, bars with cross-section of rectangular shape are followed by bars of stepped shape cross-section and vice-versa.
Analysis of High Frequency Power Transformer Windings for Leakage Inductance Calculation
Authors: Ferreira da Luz Mauricio Valencia  , Dular Patrick
Published: February 2025

This paper deals with the analysis of high frequency power transformer windings. The current and magnetic flux densities are determined by the finite element method. The considered system is a pot core transformer, to which the axisymmetric magnetic vector potential formulation is applied. The leakage inductance obtained by the finite element method is compared with the analytical one for different types of winding. The contribution of this paper is focused on the development of the analytical equations to calculate the leakage inductance.
The Influence of the Matrix Movement in a High Gradient Magnetic Filter on the Critical Temperature Distribution in the Superconducting Coil
Authors: Cieśla Antoni  , Garda Bartłomiej
Published: February 2025

The subject of the paper is an analysis of dynamical state of work of the High Gradient Magnetic Separator. HGMS requires high values of the magnetic field in big spaces. Superconducting coils are used for that field excitement. Separator works in two states. First state – static – magnetic filtration, and dynamic – exchanging the matrix. Matrix is made of ferromagnetic wool. So it influences on the field excited by the coil. During dynamical state, the matrix is taking out the filter and it affects on the field distribution in the coil windings. Unfortunately the level of temperature required to maintain the superconductivity properties locally might be dramatically lowered and it could be the cause of the serious accidents. Magnet designers have to take into consideration also the dynamical state of the magnetic filter.
Recent Developments in Magnetic Sensing
Authors: Yaman Barbaros  , Sehit Sadık  , Sahin Ozge
Published: February 2025

Measurement systems must have some properties such as sensitivity, accuracy, stability and low power consumption. New sensor types are continuously being developed according to new needs of applications besides improving measurement systems. In this study, recently developed magnetic sensors are searched. Fundamentals of new magnetic sensor types, their advantages and application areas are presented and compared in a table to form a guide for magnetic sensor users.
Application of the Magnetic Field Distribution in Diagnostic Method of Special Construction Wheel Traction Motors
Authors: Szymański Zygmunt
Published: February 2025

The paper presents a review of a special construction traction motors applied in electric and hybrid vehicle. Mathematical model of the magnetic fields distribution in traction wheel motor. Dynamic model of PMSM traction motor based on 2D magnetic flux distribution are also presented in the paper. ANSYS, JMAG and FEMM computer programs were applied in calculation of magnetic fields distribution for different faults state of the motors. On the base of magnetic field distributions were analyzed different failures situations and method of limitation their negative effects. Some laboratory experiments was realized for the traction motor.
Analysis of Structural Deformation and Vibration of Electrical Steel Sheet by Using Magnetic Property of Magnetostriction
Authors: Kitagawa Wataru  , Fujiwara Koji  , Ishihara Yoshiyuki  , Todaka Toshiyuki
Published: February 2025

Recently, it is examined with many papers about magnetostriction of electrical steel sheet and magnetostriction of transformer model. In this paper, deformation and vibration of electrical steel sheet by magnetostriction was analyzed and measured. There results were compared and examined. As results, it was reported that natural mode was provoked to force of magnetostriction.
Force Computation with the Integral Equation Method
Authors: Hafla Wolfgang  , Buchau André  , Rucker Wolfgang M.
Published: February 2025

There is a great multitude of different approaches to compute magnetic forces, each of them giving different results. Therefore, in this paper three popular force computation methods are investigated for nonlinear magnetostatic problems with the integral equation method. Computed results are compared with measurements from two setups. First, the recently presented TEAM Workshop Problem No. 33.a is used since it allows for verification of force densities. Second, the computed total magnetic force acting on a body is verified with the TEAM Workshop Problem No. 20.
Multi-frequency Eddy Current Imaging for the Detection of Buried Cracks in Aeronautical Structures
Authors: Le Diraison Yohan  , Joubert Pierre-Yves
Published: February 2025

The authors present a signal processing method dedicated to the detection of defects buried next to rivets in aeronautical lap joints. The method is based on a multi-frequency principal component analysis and is applied to the images provided by an original eddy current imager. The optimization of the method is carried out thanks to an experimental approach, and validated with the detection of buried defects, ranging from 2mm to 8mm long and 2mm to 8mm deep. An extension of the method to a classification scheme is also considered.
Automatic classification of defects with the review of an appropriate feature extraction
Authors: Romero Ramirez Alicia  , Pearson Neil  , Mason J.S.D.
Published: February 2025

A novel method for the automatic classification of defects using magnetic flux leakage inspection is presented. A technique based on geometric measures to distinguish between different defects due to petro-chemical tank corrosion is presented. In order to characterize a defect, a process of feature extraction is proposed. Principal component analysis is then used to select the most powerful set of features.
Some Experiences with Microwave Investigation of Material Defects
Authors: Faktorová Dagmar
Published: February 2025

The paper deals mainly with microwave measurement of deeper cracks in metal samples while an attempt to describe the crack as a part of the microwave line is set out. Information about the crack's properties is obtained from the reflected signal directly measured and also by means of impedance measurement.
Industrial Applications of 3MA – Micromagnetic Multiparameter Microstructure and Stress Analysis
Authors: Dobmann Gerd  , Altpeter Iris  , Wolter Bernd  , Kern Rolf
Published: February 2025

Micromagnetic NDT techniques like the measurement of the magnetic Barkhausen noise, the incremental permeability and the harmonic analysis of the tangential magnetic field allow deriving inspection procedures to online monitoring and control machinery parts and components in production processes in order to characterize mechanical properties like hardness, hardening depth, yield and tensile strength. These types of inspection procedures continuously were further developed in the last two decades so that today the second generation of system hard and software is in industrial use. The application is in steel industry where steel sheets in hot-dip-galvanizing lines were annealed after cold rolling but also in heavy plate rolling mills where after thermo-mechanical rolling special textures and texture gradients can occur. An increasing number of applications are also to find in the machinery building industry and here especially in case of machinery parts of the car supplying industry. Besides mechanical hardness determination the measurement of residual stresses and the detection of inhomogeneities in the surface of machined parts is an inspection task. In different case studies the advantage to implement a micromagnetic NDE technique into the industrial processes is discussed.
3D Nonlinear Finite Element Analysis of Electromagnetic Inspection of Defects in Steel
Authors: Takahashi N.  , Gotoh Y.
Published: February 2025

The electromagnetic inspection technology is commonly used to evaluate defects in steel in various power generation plants because of its ability to detect quickly. In this paper, the electromagnetic inspection methods using an ac magnetic field, or a biased ac field are proposed. The behavior of the flux in steel is examined using 3-D FEM that takes into account the initial magnetization curve, hysteresis (minor loop) and eddy currents in order to improve the inspection method.
Analysis of Barkhausen Noise Characteristics and Mechanical Properties on Cold Rolled Low Carbon Steel
Authors: Kikuchi Hiroaki  , Koshika Tomoki  , Liu Tong  , Kamada Yasuhiro  , Ara Katsuyuki  , Kobayashi Satoru  , Takahashi Seiki
Published: February 2025

Low carbon steel specimens cold rolled at ratios of 0–40 % have been examined comprehensively by magnetic Barkhausen noise (MBN) method, and their microstructure were studied by transmission electron microscope. In order to correlate MBN parameters with those mechanical properties, Vickers hardness and ductile-brittleness transition temperature (DBTT) were also evaluated. MBN energy and rms voltage rise rapidly with cold rolling below 10 %, and saturate at higher rolling ratio. This phenomenon is attributed to the combined effects of cell texture and dislocation density. It is also found that good correlation between MBN parameters and Vickers hardness, DBTT.
ND-materials characterization of neutron-induced embrittlement in German nuclear reactor pressure vessel material by micromagnetic NDT techniques
Authors: Dobmann Gerd  , Altpeter Iris  , Kopp Melanie  , Rabung Magdalena  , Hübschen Gerhard
Published: February 2025

Depending on the neutron fluence and the special design of the pressure vessel of nuclear power plants (NPP) the microstructure of the steels change by neutron induced embrittlement. Embrittlement is on the basis of vacancies and Curich precipitates which in the size range of 1–3 nm contribute with coherent residual stresses of the 3rdkind to an increase in hardness and strength (yield strength and tensile strength) as well as with a reduction of the upper shelf value of Charpy energy and a shift in the brittle-to-ductile transition temperature to higher temperatures. Micromagnetic investigations sponsored by the German minister of economics were performed at full Charpy specimen and material of the last generation of German NPP in order to characterize the material degradation. The contribution reports to the results obtained by the application of the Micromagnetic-, Multiparameter-, Microstructure-, and stress-Analysis (3MA) and the magnetostrictive excitation of ultrasound using an EMAT. Both technologies document potential to be further developed to an in-service inspection technique.