Bulletin of NTU "KhPI". Series: Problems of Electrical Machines and Apparatus Perfection. The Theory and Practice / Вісник Національного технічного університету "ХПІ". Серія: Проблеми удосконалювання електричних машин і апаратів. Теорія і практика
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Cognitive diagnostic modelling in healthcare professions education: an eye-opener
No full textCriticisms about psychometric paradigms currently used in healthcare professions education include claims of reductionism, objectification, and poor compliance with assumptions. Nevertheless, perhaps the most crucial criticism comes from learners' difficulty in interpreting and making meaningful use of summative scores and the potentially detrimental impact these scores have on learners. The term "post-psychometric era" has become popular, despite persisting calls for the sensible use of modern psychometrics. In recent years, cognitive diagnostic modelling has emerged as a new psychometric paradigm capable of providing meaningful diagnostic feedback. Cognitive diagnostic modelling allows the classification of examinees in multiple cognitive attributes. This measurement is obtained by modelling these attributes as categorical, discrete latent variables. Furthermore, items can reflect more than one latent variable simultaneously. The interactions between latent variables can be modelled with flexibility, allowing a unique perspective on complex cognitive processes. These characteristic features of cognitive diagnostic modelling enable diagnostic classification over a large number of constructs of interest, preventing the necessity of providing numerical scores as feedback to test takers. This paper provides an overview of cognitive diagnostic modelling, including an introduction to its foundations and illustrating potential applications, to help teachers be involved in developing and evaluating assessment tools used in healthcare professions education. Cognitive diagnosis may represent a revolutionary new psychometric paradigm, overcoming the known limitations found in frequently used psychometric approaches, offering the possibility of robust qualitative feedback and better alignment with competency-based curricula and modern programmatic assessment frameworks
The Relevance of Stability and Change of Achievement Goals for Self-regulated Motor Learning Processes and Outcomes
No full textSelf-regulated motor learning is a frequent and important achievement activity in sport and exercise contexts. Therein, individual learners’ achievement goals can be considered relevant for motor learning processes and outcomes. To better understand their role, we first examined the temporal stability of achievement goals during self-regulated motor learning. Next, we tested the relevance of the goals and their temporal variability for the learning process (learning time, effort, and motivational problems) and learning outcomes (performance and continuance intentions). To this end, 93 individuals completed a total of 1,017 daily diary entries about their goals (learning-approach, performance-approach, performance-avoidance, work-avoidance goals) and learning processes across sixteen days while learning juggling basics. Afterwards, they completed a post-test assessing their learning outcomes. Multi-level analyses indicated that goals contained both temporally stable and temporally variable fractions that were both relevant for learning processes. For learning outcomes, not only mean levels, but also temporal trends mattered
Construction and Validation of a Short Multidisciplinary Research Performance Questionnaire (SMRPQ)
No full textResearch is often specialised and varies in its nature between disciplines, making it difficult to assess and compare the performance of individual researchers. Specific qualitative and quantitative indicators are usually complex and do not work equally well for different research fields. Therefore, the aim of the present study was to develop an economical questionnaire that is valid across disciplines. We constructed a Short Multidisciplinary Research Performance Questionnaire (SMRPQ), with which researchers can briefly report 11 quantitative and qualitative performance aspects from four areas (research quality, facilitation, transfer/exchange, and reputation) in relation to their peer reference groups (fellow researchers with the same status and discipline). To validate this questionnaire, 557 German researchers from Physics, History, and Psychology fields (53% male, 34% post-docs, 19% full professors) completed it, and for the purpose of convergent and discriminant validation additionally made assessments regarding specific quantitative and qualitative indicators of research performance as well as affective, cognitive, and behavioural aspects of their research activities (perceptions of positive affect, help-seeking, procrastination). The results attested reliable measurement, endorsed the postulated structure of the newly developed instrument, and confirmed its invariance across the three disciplines. The SMRPQ and the validation measure were strongly positively correlated, and both demonstrated similar associations with affect, cognition, and behaviour at work. Therefore, it can be considered a valid and economical approach for assessing research performance of individual researchers across different disciplines, especially within nomothetic research (e.g. regarding personal antecedents of successful research)
Supporting Self-regulated Learning with Digital Media using Motivational Regulation and Metacognitive Prompts
No full textStudying with digital media, learners often struggle because of inadequate self-regulation. Previous research presented clear evidence of metacognitive prompts being effective in supporting learning with digital media. This study examines the potential of motivational regulation prompts, which are assumed to additionally support self-regulated learning. During a 50-min learning session in a digital media learning environment, 215 university students received either no prompts, only metacognitive prompts, only motivational regulation prompts, or both types of prompts. Task value, metacognitive control, task-related learning activities, and knowledge were assessed at a pretest, posttest, and follow-up. The results replicated known positive effects of metacognitive prompts and revealed additional supportive effects of motivational regulation prompts on all dependent variables. Path modeling of the experimentally induced changes was in line with a theoretical model specifying proximal and distal effects of both prompts. Altogether, this indicates that especially motivational regulation prompts could be an effective scaffold to support SRL with digital media
Stockpiling during the COVID-19 pandemic as a real-life social dilemma: A person-situation perspective
No full textPrior research using economic games has shown that personality drives cooperation in social dilemmas. In this study, we tested the generalizability of these findings in a real-life social di-lemma during the COVID-19 pandemic, namely stockpiling in the presence of low versus high resource scarcity. Honesty-Humility was negatively related to stockpiling intentions and justi-fiability of stockpiling. Moreover, we found a positive albeit weaker effect of Emotionality on stockpiling intentions. Victim Sensitivity was mostly positively associated with stockpiling intentions. None of the personality traits interacted with resource scarcity to predict stockpil-ing. Our findings replicate established associations between personality and cooperation in a real-life social dilemma, and suggest that the characteristics of interdependent situations during a pandemic additionally afford the expression of Emotionality
A Methodological Approach to Designing a Theory: The Journey of the Four Zone Professional Learning Model
No full textThe Four Zone Professional Learning Model is a practical, comprehensive approach to striving towards equity through professional learning within gifted education programs. Grounded in equity literacy and funds of knowledge frameworks, and in best practices in culturally responsive gifted professional learning, the zones address the knowledge and skills necessary for proficient teachers of the gifted and address the process of systemic change. The model was designed and developed over several years utilizing the plan-study-do-act action research model; this article discusses the methodological evolution of the model, the research and theoretical frameworks in which it is grounded, and future implications
Розрахунок обмотувальних даних котушок включення та відключення бістабільного поляризованого електромагніта для вакуумного контактора середніх напруг
Get PDFMedium voltage vacuum contactors consist of switching and drive modules. When developing or improving the designs of contactors, the switching module must meet the requirements set forth by their manufacturers. In accordance with these requirements, a drive module is being developed, which consists of a mechanical system and an electromagnet. The operation of the mechanical system of the contactor depends on correctly selected contact springs, and the operation of the electromagnet depends on traction forces during switching operations. The design of a vacuum contactor with a bistable polarized electromagnet with two ON and OFF coils is considered in the article. The counteracting characteristic of the mechanical system of the contactor is constructed and the forces acting on the electromagnet in the ON and OFF positions of the contactor are determined. The FEMM model of a bistable polarized electromagnet was developed and the minimum MMF value of the ON and OFF windings was determined. The resulting traction characteristic of a bistable polarized electromagnet is constructed at the minimum MMF value of the ON and OFF winding sand the working gap. It was determined that when performing the switching operation and using the ON and OFF winding at the same time, it was possible to reduce the MMF of the electromagnet operation. The winding data of the ON and OFF coils were calculated at different values of the nominal diameter of the wire and the voltage of the power supply network, and, in accordance with this, the minimum value of the MMF of the windings was determinedВакуумні контактори середніх напруг складаються з комутаційного та привідного модулів. При розробці або удосконалені конструкцій контакторів комутаційний модуль повинен відповідати вимогам, що висуваються їх виробниками. У відповідності з цими вимога розробляється привідний модуль, який складається з механічної системи та електромагніта. Робота механічної системи контактора залежить від правильно обраних контактних пружин, а робота електромагніта – від тягових зусиль при виконанні комутаційних операцій. В роботі розглянуто конструкцію вакуумного контактора з бістабільним поляризований електромагнітом з двома котушками включення та відключення. Побудовано протидіючу характеристику механічної системи контактора та визначено сили, що діють на електромагніт у включеному та відключеному положеннях контактора. Розроблено FEEM модель бістабільного поляризованого електромагніта та визначено мінімальне значення МРС обмоток включення та відключення. Побудовано результуючу тягову характеристику бістабільного поляризованого електромагніта при мінімальному значенні МРС обмоток включення та відключення і робочому зазорі. Визначено, що при виконанні комутаційної операції та використанні спільно обмоток включення і відключення вдалося зменшити МРС спрацьовування електромагніта. Проведено розрахунок обмотувальних даних котушок включення та відключення при різних значеннях номінального діаметру проводу та напруги мережі живлення і, у відповідності з цим, визначено мінімальне значення МРС обмоток
Cooperative phenotype predicts climate change belief and pro-environmental behaviour
No full textUnderstanding the psychological causes of variation in climate change belief and pro-environmental behaviour remains an urgent challenge for the social sciences. The “cooperative phenotype” is a stable psychological preference for cooperating in social dilemmas that involve a tension between individual and collective interest. Since climate change poses a social dilemma on a global scale, this issue may evoke similar psychological processes as smaller social dilemmas. Here, we investigate the relationships between the cooperative phenotype and climate change belief and behaviour with a representative sample of New Zealanders (n = 897). By linking behaviour in a suite of economic games to self-reported climate attitudes, we show robust positive associations between the cooperative phenotype and both climate change belief and pro-environmental behaviour. Furthermore, our mediation analyses support a motivated reasoning model in which the relationship between the cooperative phenotype and pro-environmental behaviour is fully mediated by climate change belief. These findings suggest that common psychological mechanisms underlie cooperation in both micro-scale social dilemmas and larger-scale social dilemmas like climate change
Аналіз конструкцій приводних механізмів вакуумних контакторів середніх напруг
Get PDFOne of the main elements of medium voltage vacuum contactors is the drive mechanism, which includes an electromagnet. In existing models of contactors, two types of electromagnets are used: monostable non-polarized electromagnets with a return spring or bistable polarized without a return spring. It was found that the use of polarized electromagnets in combination with a microprocessor control system expands the functionality of the contactor and makes it possible to reduce the energy consumption of the electromagnets, their overall dimensions and weight, while achieving significant armature holding forces. The designs of polarized electromagnets, which were developed at the Department of Electrical Apparatus in recent years, are considered. Their shortcomings were identified and a new design of a bistable polarized electromagnet was proposed, a computer model of the contactor developed in the KOMPAS-3D package was built. The counteracting characteristic of the mechanical system of the contactor, which is brought to the axis of the electromagnet and the stroke of the armature, is constructed, the forces that must be created by the electromagnet in the on and off position for reliable operation are determined. The FEMM model of the experimental sample of a bistable polarized electromagnet was developed and the calculation was carried out in the on and off positions. The possibility of using a new design of an electromagnet in a medium-voltage vacuum contactor has been confirmed.Одним з головних елементів вакуумних контакторів середніх напруг є приводний механізм до складу якого входить електромагніт. В існуючих моделях контакторів використовуються два типи електромагнітів: моностабільні неполяризовані електромагніти з поворотною пружиною або бістабільні поляризовані без поворотної пружини. Виявлено, що використання поляризованих електромагнітів у поєднанні з мікропроцесорною системою керування розширює функціональні можливості контактора та дає змогу зменшити енергоспоживання електромагнітів, їх габаритні розміри та вагу, при цьому досягаючи значних сил утримання якоря. Розглянуто конструкції поляризованих електромагнітів, що були розроблені на кафедрі електричних апаратів НТУ «ХПІ» впродовж останніх років. Виявлено їх недоліки та запропоновано удосконалену конструкцію бістабільного поляризованого електромагніта, побудовано комп’ютерну модель контактора розроблену в пакеті КОМПАС-3D. Побудовано протидіючу характеристику механічної системи контактора, яка наведена до осі електромагніта та ходу якоря, визначено сили, які повинен створювати електромагніт у включеному та відключеному положеннях для надійного спрацьовування. Розроблено FEMM модель дослідного зразка бістабільного поляризованого електромагніта та проведено розрахунок у включеному і відключеному положеннях. Підтверджено можливість використання нової конструкції електромагніта у вакуумному контакторі середніх напруг
Аналіз апаратного захисту асинхронних двигунів з короткозамкненим ротором напругою до 0,66 кВ від перенавантажень та перегріву
Get PDFAn analysis of the hardware protection of asynchronous motors with a short-circuited rotor with a voltage of up to 0,66 kV against overloads and overheating, implemented in accordance with modern standards, was carried out. The causes and factors of engine overheating and the functional features of the specified protection devices are considered. Conclusions were made regarding the effectiveness of certain types of protection against overloads and overheating of engines and their combination in order to increase the reliability of protection. The most promising directions for improvement of hardware protection against overload and overheating of asynchronous motors have been establishedПроведено аналіз апаратного захисту асинхронних двигунів з короткозамкненим ротором напругою до 0,66 кВ від перевантажень та перегріву, реалізованого у відповідності із сучасними стандартами. Розглянуто причини і фактори перегріву двигунів та функціональні особливості вказаних апаратів захисту. Зроблено висновки стосовно ефективності окремих видів захисту двигунів від перевантажень та перегріву і їх поєднання з метою підвищення надійності захисту. Встановлено найбільш перспективні напрямки удосконалення апаратного захисту від перевантаження та перегріву асинхронних двигуні