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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Моделювання електричних і магнітних перехідних процесів у системі з індуктором і статором електричних машин змінного струму
Full text linkA brief review of the issue of diagnosing the condition of the insulation structure of electrical machines with classical distributed windings is presented. The rationale and relevance of developing and implementing new, innovative diagnostic and testing methods are provided. The proposed method possesses significant diagnostic features that are absent in other currently used methods. The main difference lies in the creation of high test overvoltages through a rapid change in magnetic fluxes in inductively coupled circuits, one of which is an external sensor-inductor, and the second is a part of the magnetic core with a defective or non-defective winding. A simple and convenient testing scheme is proposed, which can be implemented using appropriate measuring equipment. A comprehensive set of theoretical and experimental studies of the inductor–stator system with a winding was conducted using the Matlab Simulink software package and the field method in a two-dimensional problem formulation in the COMSOL Multiphysics software package. Experimental studies were also conducted on a real sample in the form of a stator of a low-power general-purpose induction motor with a random winding, utilizing the developed testing scheme and device. The theoretical and experimental studies show sufficient convergence of results for engineering purposes. The possibility of achieving test overvoltages exceeding 100 V per turn with low energetic impact on defective zones is theoretically and experimentally substantiated, which ensures a minimal destructive effect during diagnostics. Substantial results were obtained for further research and development of the field of insulation condition diagnostics using inductive impulse methods. It is demonstrated that the proposed method will be useful for diagnosing the insulation condition of electrical machine windings in a disassembled state during manufacturing and repair processes.Зроблено короткий огляд питання діагностування стану ізоляційної конструкції електричних машин з розподіленим обмотками класичної конструкції. Наведено обґрунтування та актуальність розробки і впровадження нових інноваційних методів діагностики і випробувань. Запропонований метод має суттєві діагностичні ознаки, яких немає у інших використовуваних на сьогодні методах. Основною відмінністю є створення високих випробувальних перенапруг шляхом швидкої зміни магнітних потоків в індукційно пов’язаних контурах один з яких виносний датчик-індуктор, а другий – частина магнітопроводу з дефектною або бездефектною обмоткою. Запропоновано просту і зручну схему проведення випробувань, яку можна реалізувати відповідною вимірювальною апаратурою. Проведено комплекс теоретичних і експериментальних досліджень системи індуктор–статор з обмоткою за допомогою програмного пакету MATLAB/Simulink та польовим методом у двовимірній постановці задачі у програмному пакеті COMSOL Multiphysics. Також проведено експериментальні дослідження на реальному зразку у вигляді статора малопотужного асинхронного двигуна загального призначення із всипною обмоткою за допомогою розробленої випробувальної схеми та приладу. Теоретичні та експериментальні дослідження мають достатню збіжність результатів для інженерних цілей. Теоретично та експериментального обґрунтована можливість отримання випробувальних перенапруг більше 100 В на виток при низьких енергетичних впливах на дефектні зони, що забезпечує мінімальний руйнівний ефект під час діагностики. Отримано ґрунтовні результати для подальших досліджень та розвитку напрямку діагностування стану ізоляції індукційними імпульсними методами. Показано, що запропонований метод буде корисним при діагностуванні стану ізоляції обмоток електричних машин в розібраному стані в процесі виробництва і ремонту
Technological Change, Inequality, and Social Unrest: Evidence from Agriculture
No full textTechnological change is often biased, producing wealth that is distributed unequally across social groups. Does technology-driven inequality also contribute to social unrest? Such concerns date to Karl Marx, but have acquired renewed salience in the age of artificial intelligence and robots. This paper draws lessons from a major technological revolution in agriculture: the green revolution. In India, the spread of a new crop technology, high-yielding variety (HYV) crops, improved agricultural productivity, but also generated rising inequality between landowners and the rural poor. Drawing on a panel dataset linking district-level estimates of HYV crop adoption to digitized crime records, this paper provides evidence that the spread of the new crop technology contributed to a wave of banditry (dacoity), a crime associated with class conflict in agrarian societies. The technology-violence relationship was concentrated in districts with colonial-era landlord-based (zamindari) land tenure systems, plausibly because of less pass-through of agricultural productivity improvements to wages
Eupsychian Theory I: Reclaiming Maslow and Rejecting The Pyramid - The Circle of Seven Essential Needs
No full textIn 1943, Abraham Maslow presented a now widely accepted theory of human motivation. Later, he began to develop a theory of human development, a Eupsychian theory of human flourishing with his theory of needs at the center. This theory was shortly represented by the iconic Pyramid of Needs. Building upon the work of Abraham Maslow, this article rejects the pyramid of needs as an ideologically rooted, sanitized, and stripped-down version of Maslow’s nascent Eupsychian Theory. Instead, the article proposes an Indigenous-rooted Circle of Seven Essential needs as the core of a sophisticated and integrative theory of human development, human potential, and human flourishing, a theory that Maslow was in the process of developing before his untimely death and that, given his known interest in Indigenous communities, more in line with the direction of Maslow’s early thinking
Movies' Content Features Predict the Personalities of Their Fans
No full textMovies are a central form of entertainment and cultural expression, yet little is known about how their content aligns with the psychological traits of their audiences. We investigate this by linking movie characteristics and contents with the Big Five personality measures of social-media users who “liked” them. Our analysis shows that movie content, captured via text keywords, predicts audience personalities beyond genre, demographics, and other attributes like quality and popularity. An online experiment confirms these predictions generalize across new movies, audiences, and preference elicitation methods. We further provide fine-grained mappings between personality and movie features, including quality, popularity, genre, psychological themes (e.g., leisure), and unique concepts (e.g., adultery). Our findings reveal systematic links between personality and movie preferences, showing that people favor content that resonates with their thoughts, emotions, and behaviors. This research enables scalable, automated audience psychographic assessment based on content features, offering deeper insights into personality-driven media preferences
Inequality in People’s Minds: An integrative psychological framework of perceptions of economic inequality
No full textPeople’s perceptions of economic inequality are important predictors of their political attitudes and behaviors. Scholars across the social sciences have worked to understand people’s (mis)perceptions of inequality. Yet, scholars currently lack a common framework for integrating emerging findings and conceptualizing how these perceptions are formed. Here, we propose an integrative framework to help researchers highlight the psychological processes underlying how inequality is perceived. We draw on theories of perception, cognition, developmental, and social psychology to identify five interlinked, iterative components of the inequality perception process: (1) access to inequality cues, (2) attention to these cues, (3) comprehension of these cues, (4) motivated processing of these cues, and (5) meaningful summary representation of inequality. Our framework provides a roadmap for integrating research across disparate fields, making sense of current findings, and identifying novel challenges to advance future research
No effect of variety on perceived quantity: Evidence from six studies
No full textRedden and Hoch (2009) found that variety in a set of items robustly decreased the perceived quantity of the sum of these items across multiple studies. For example, a set of multicolored M&M’s was estimated to contain fewer M&M’s than an equally large set of single-colored M&M’s (e.g., Redden & Hoch, 2009, Study 3). We conducted six close replication studies of the studies reported by Redden and Hoch and did not find this effect in any of them. A meta-analysis of the four original studies and 6 replication studies (N = 1,383) revealed no evidence for the phenomenon that variety reduces perceived quantity.
Published version:
Röseler, L., Felser, G., Asberger, J., & Schütz, A. (2024). The Effect of Variety on
Perceived Quantity: Failures to Replicate Redden and Hoch (2009). MetaPsychology, 8. https://doi.org/10.15626/MP.2020.263
Modelling and Simulating Action Dynamics in Underconstrained Tasks in Virtual Reality
No full textConsistently achieving a desired level of task performance across contextual conditions requires behavioral adaptability. In this paper we showcase a VR application based on a previous 'in-real-life' task that produces data analyzable for flexibility & stability of body movements and correlated performance
Computación, análisis e interpretación de señales eléctricas del cerebro humano en el dominio del tiempo: 90 años de Electrofisiología Cognitiva
No full textLa invención de la electroencefalografía (EEG) marcó un hito histórico tecnológico/metodológico que posicionó a la actividad eléctrica cerebral de gran escala como nuevo objeto epistemológico para el estudio de fenómenos cognitivos, inaugurando la subdisciplina de la Electrofisiología Cognitiva. Este documenta una historia breve de la Electrofisiología Cognitiva, desde los orígenes de la Electrofisiología Cognitiva, su apogeo científico/social en la década del 1980, hasta la invención de la resonancia magnética funcional. Posteriormente, revisamos aspectos metodológicos y teóricos predominantes en la literatura respecto al potencial relacionado a eventos (event related potential, ERP). Además, se provee software para computar ERP y datos de muestra.
Actualmente, las señales neurofisiológicas humanas adquiridas no-invasivamente siguen siendo una de las principales formas de estudiar correlatos neurales de fenómenos cognitivos. El presente trabajo busca promover las herramientas necesarias para el entendimiento sobre la computación e interpretación de estas señales cerebrales
A Global Experiment on Motivating Social Distancing during the COVID-19 Pandemic
No full textFinding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e. a controlling message) compared to no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly-internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared to the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly-internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing: Controlled motivation was associated with more defiance and less long-term behavioral intentions to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
Електромагнітна сумісність технічних об‘єктів і систем: попередній огляд деяких програмних засобів для комп’ютерного моделювання
Full text linkComputer modelling is an integral part of solving modern problems of electromagnetic compatibility of technical as well as biological objects and systems. For computer modelling of the relevant electromagnetic processes and phenomena, it is advisable to use professional commercial software products that have proven themselves well, either specifically or in the course of electromagnetic compatibility research. The article is devoted to a preliminary overview and comparison of commercial software products available on the market for possible use in performing computational studies in the field of electromagnetic compatibility of technical objects and systems, primarily in relation to microprocessor control systems of modern low, medium and high voltage switching devices. On this basis, a preliminary selection of specific software products for use in performing the relevant computational studies is made.Комп‘ютерне моделювання є невід‘ємною складовою розв’язання сучасних задач електромагнітної сумісності технічних, а також біологічних об’єктів і систем. Для комп’ютерного моделювання відповідних електромагнітних процесів і явищ доцільно використовувати професійні комерційні програмні продукти, які добре зарекомендували себе саме або у тому числі у ході дослідження електромагнітної сумісності. Стаття присвячена попередньому розгляду та порівнянню присутніх на ринку комерційних програмних продуктів для можливого застосування при виконанні розрахункових досліджень у сфері електромагнітної сумісності технічних об’єктів і систем, в першу чергу стосовно мікропроцесорних систем керування сучасної комутаційної апаратури низької, середньої та високої напруг. На цій основі робиться попередній вибір конкретних програмних продуктів для застосування при виконанні відповідних розрахункових досліджен