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RF, Microwave, and Millimeter Wave Devices and Circuits and Their Applications
No full textThis Special Issue, titled “RF, Microwave, and Millimeter Wave Devices and Circuits and Their Applications”, presents a comprehensive overview of recent innovations in the design of high-frequency systems and of their multidisciplinary applications. The selected contributions span a wide array of domains—from power amplifiers, mixers, and phase shifters to advanced antenna arrays and metamaterial-inspired filters—demonstrating how the latest breakthroughs in circuit topology, device architecture, and packaging techniques are enabling the creation of high-performance systems at frequencies ranging from only a few to tens of gigahertz. We hope that this Special Issue will serve as both a valuable reference and a source of inspiration for engineers, researchers, and industry practitioners working at the frontier of RF, microwave, and millimeter wave technologies
La conservation des aliments — Vers plus de durabilité et de naturalité
No full textProducts of plant or animal origin evolve under the action of biochemical and microbial reactions. To limit their deterioration, preservation methods have been developed since prehistoric times, and their principles are still the basis of techniques used in the food industry today. These processes are indispensable, but Western consumers tend to question them for various reasons: sustainability of the processes, naturalness of the preservatives and impact on our health. Based on current knowledge in the field of food science, this book provides an insight into the contribution of preservation processes to healthy, sustainable and available food. It presents their modes of action, the questions they raise and the answers provided by research. The use of cold or heat, fermentation or biopreservation, the role and sustainability of packaging, food formulation and life-cycle analyses are all topics addressed through the prism of current agri-food resources. The authors also highlight more recent processes and explore the idea of combining different methods to meet tomorrow's food challenges. This book is part of a wider reflection on the evolution of our food. It is aimed at all those — consumers, teachers, students, decision-makers — who want to better understand how today's technological choices can influence the future of our food, and therefore that of our health and our environment
Flachbettsiebdruck endkonturnaher Magnetbleche für elektrische Maschinen
No full textDie Bedeutung der ressourceneffizienten Herstellung sowie des energieeffizienten Betriebs elektrischer Maschinen steigt in Folge des verstärkten Einsatzes erneuerbarer Energien, des Hochlaufs der Elektromobilität sowie der zunehmend automatisierten und elektrifizierten Industrie stetig an. Elektromotoren stellen in der Europäischen Union den größten Verbraucher elektrischer Energie dar. Daher besteht ein großer Forschungs- und Entwicklungsbedarf an neuen Herstellungsprozessen und Materialien, um den Wirkungsgrad elektrischer Maschinen zu verbessern. Eisenverluste, die in den Stator- und Rotor-Blechpaketen elektrischer Maschinen auftreten, stellen bei elektrischen Antriebssystemen für batterieelektrische Fahrzeuge sowie viele performante Industrieanwendungen die dominante Verlustquelle dar. Die Herstellung von Blechpaketen erfolgt konventionell großserientechnisch mittels kombinierter Stanz- und Paketiertechnologien. Diese verursachen große Mengen an Ausschuss durch Blechverschnitt, zudem werden die Randbereiche der Magnetbleche plastisch verformt und somit das Material geschädigt. Die vorliegende Dissertation betrachtet daher einen neuen additiven Fertigungsprozess von Elektroblechen für Stator-Blechpakete mittels Flachbett-Siebdruck und anschließender Sinterung. Dieser Prozess bietet eine große geometrische Gestaltungsfreiheit für das Blechdesign, ermöglicht eine breite Legierungsauswahl entsprechend der spezifischen Anforderungen und führt durch endkonturnahe Herstellung zu einem hohen Materialausnutzungsgrad. Der Gesamtprozess wird ausgehend vom Eisenpulver bis zum gesinterten Magnetblech ganzheitlich betrachtet und geeignete Materialien und Prozessparameter systematisch untersucht
Mehr als Ausbildung, mehr als Studium
No full textDie Veröffentlichung der Autoren Euler, Naeve-Stoß und Severing untersucht, wie sich die Rolle der dualen Berufsausbildung verändert, seit rund die Hälfte eines Jahrgangs eine Hochschulzugangsberechtigung erwirbt und zwischen Studium und Ausbildung wählen kann. Trotz rückläufiger Ausbildungsneuzugänge und steigender Studienanfängerzahlen stieg der Anteil Studienberechtigter unter den Ausbildungsanfänger:innen von 15,8 % (2000) auf 28,5 % (2022). Zugleich hat sich das duale Studium vervielfacht, oft als praxisintegrierte Variante ohne klassische Berufsausbildung. Im Zentrum steht die "studienintegrierende Ausbildung" (SiA): Eine gemeinsame Grundstufe verzahnt duale Ausbildung mit studienbezogenen Inhalten; danach entscheiden Lernende zwischen Berufsabschluss, Studienabschluss oder Doppelabschluss. Die Begleitung in Hamburg und NRW zeigt die Bedeutung von Lernortkooperation sowie Organisations- und Personalentwicklung. Kernelement ist ein Bildungsweg-Coaching zur Entscheidungsunterstützung
Estudio comparativo del efecto de la fertilización orgánica e inorgánica sobre el crecimiento y productividad del cultivo de Ají (Capsicum annuum)
No full textFertilizers are made from organic or inorganic materials added to cropping systems to supply one or more essential nutrients. Inorganic fertilizers promote optimal plant development by providing nutrients in readily available forms, while organo-mineral fertilizers offer a sustainable alternative to enhance agricultural productivity by preserving soil quality and being accessible to smallholders. This study aimed to compare the effects of organic, inorganic, and mixed fertilization on the growth and productivity of the chili pepper crop (Capsicum annuum) in soils from Carabobo State, Venezuela. A completely randomized block design was used with four treatments: control (T0, Bocashi), organic (T1, humic acids), inorganic (T2, NPK formulations), and a 1:1 mixture of organic and inorganic fertilizers (T3). The evaluated variables included physical, chemical, and biological soil properties, biometric parameters of the crop, and productivity. Results showed that all treatments significantly improved soil conditions compared to the initial state. Treatment T3 was the most effective in increasing organic matter content, moisture retention capacity, and cation exchange capacity, also promoting greater plant height and stem diameter, as well as a higher number of fruits per plant. T0 and T1 stood out in increasing soil basal respiration, indicating higher microbial activity. In terms of productivity, T0 showed the highest value (1.53 kg/ha), followed by T3 (1.46 kg/ha), while T1 had the lowest productivity (1.09 kg/ha). It is concluded that the combination of organic and inorganic fertilization optimizes nutrient availability and improves both soil and crop growth conditions, contributing to more sustainable and efficient agricultural practices.PublishedLos fertilizantes están hechos de materiales orgánicos o inorgánicos que se agregan a los sistemas de cultivo para suministrar uno o más nutrientes esenciales. Los fertilizantes inorgánicos pueden favorecer un desarrollo óptimo de las plantas al proporcionar nutrientes de rápida disponibilidad, mientras que los fertilizantes orgánicos son una alternativa sostenible que mejora la producción agrícola preservando la calidad del suelo, además de ser más accesibles para los pequeños productores. El presente estudio tuvo como objetivo comparar el efecto de la fertilización orgánica, inorgánica y mixta sobre el crecimiento y la productividad del cultivo de ají (Capsicum annuum), en suelos del estado Carabobo, Venezuela. El diseño experimental consistió en un esquema de bloques completamente al azar, con cuatro tratamientos: control (T0, Bocashi), orgánico (T1, ácidos húmicos), inorgánico (T2, formulaciones NPK) y mezcla 1:1 de orgánico e inorgánico (T3). Las variables evaluadas incluyeron propiedades físicas, químicas y biológicas del suelo, además de parámetros biométricos del cultivo y productividad. Los resultados indicaron que todos los tratamientos mejoraron significativamente las condiciones del suelo respecto al estado inicial. El tratamiento T3 fue el más eficaz en incrementar la materia orgánica, la capacidad de retención de humedad y la capacidad de intercambio catiónico, promoviendo además un mayor crecimiento en altura y diámetro del tallo, y un mayor número de frutos por planta. T0 y T1 destacaron en el aumento de la respiración basal del suelo, reflejo de mayor actividad microbiana. En términos de productividad, T0 alcanzó el valor más alto (1,53 kg/ha), seguido de T3 (1,46 kg/ha), mientras que T1 presentó la menor productividad (1,09 kg/ha). Se concluye que la combinación de fertilización orgánica e inorgánica optimiza la disponibilidad de nutrientes y mejora las condiciones edáficas y de cultivo, lo que contribuye a una agricultura más eficiente y sostenible
Patrimonio Esistente. Città Futura
No full textThis volume presents the outcomes of three theses in Architectural and Urban Design, defended in the 2023/24 and 2024/25 academic years within the Master’s degree in Architecture (Arc5UE) at the Department of Architecture, University of Naples Federico II. At the core of the discussion is the transformation of existing heritage as a strategic tool for urban regeneration. Each project tackles a specific typology — silos, barracks, cisterns — structures originally conceived to contain goods, people, or water, which today are opened to new purposes, becoming spaces for community life, housing, culture, and production.The design approach transcends the scale of the standalone building to establish relationships at the neighborhood and city scale: physical restoration intertwines with social, cultural, and economic dimensions, healing the fractures caused by disuse and abandonment. Thus, existing heritage is reinterpreted as true design material, capable of generating new urban scenarios where historical continuity and formal innovation converge.The volume therefore positions itself as an observatory of the multiple trajectories urban regeneration can assume: it demonstrates how design, as a critical-operational device, can restore centrality to marginalised urban fragments, converting temporary voids into strategic hubs of connection and exchange. From this perspective, the adaptive reuse of former silos, barracks, and cisterns becomes a paradigm of regenerative continuity, capable of reinventing the ordinary and reshaping the future of contemporary cities.PublishedIl volume presenta gli esiti di tre ricerche di tesi in Progettazione Architettonica e Urbana, discusse negli a.a. 2023/24 e 2024/25 nel corso di laurea magistrale a ciclo unico in Architettura (Arc5UE) del Dipartimento di Architettura dell’Università degli Studi di Napoli Federico II. Al centro del confronto c’è la trasformazione del patrimonio esistente quale leva strategica per la rigenerazione urbana. Ciascun progetto si misura con una tipologia specifica – silos, caserme, cisterne –strutture originariamente concepite per contenere merci, persone o acqua, che oggi si aprono a nuovi contenuti, divenendo luoghi per la collettività, l’abitare, la cultura, la produzione. L’approccio progettuale supera la dimensione dell’oggetto architettonico per instaurare relazioni su scala di quartiere e di città: il recupero fisico si intreccia con le declinazioni sociali, culturali ed economiche, sanando le fratture causate da dismissione e abbandono. Così il patrimonio esistente si trasforma in vera e propria materia di progetto, capace di generare nuovi scenari urbani in cui si coniugano continuità storica e innovazione formale.Il volume si propone così come osservatorio delle molteplici traiettorie che la rigenerazione urbana può assumere: dimostra come il progetto, inteso quale dispositivo critico-operativo, possa restituire centralità a porzioni di città marginalizzate, convertendo vuoti temporanei in nodi strategici di connessione e scambio. In questa prospettiva, il riuso di ex silos, caserme e cisterne diventa paradigma di una continuità rigeneratrice, capace di reinventare l’ordinario e di rilanciare il futuro della città contemporane
Chapter L’Anfiteatro di Boboli: concezione e trasformazioni di uno spaz io monumentale
No full textThe here collected contributions relating to the 46th International Conference of the Representation Disciplines Teachers, organized jointly by Sapienza University of Rome, Roma Tre University, and San Raffaele Roma University, aim to offer the scientific community a reflection on the theoretical and methodological aspects related to the concept of èkphrasis, a term that, in the field of representation, concerns descriptive, analogical, and digital activities that generate new knowledge in several areas of application. The Conference aims to place at the center of the discussion an interpretation of the concept of research that, without neglecting an idea of study, protection, and enhancement of environmental and cultural heritage, focuses on the needs of contemporary society and its possible developments, making use of innovative theoretical, methodological, and operational activities, including those characterized by an interdisciplinary approach. According to this interpretation, research can also be seen as a foreshadowing of the definition and testing of experimental proposals aimed at exploring new areas of investigation: this opens up imaginative and utopian perspectives in the relationship between the sciences, the arts, and the disciplines that contribute to common goals, through the experimentation of methods, techniques, and languages for conceiving, prefiguring, designing, and representing
Construyendo futuros: didáctica de las ciencias económicas desde los problemas sociales en la educación básica y media
No full textHow can we educate citizens with a critical and forward-looking vision of the economy from the early stages of schooling? This book presents an innovative study that examines the teaching and learning of economic sciences through socially relevant problems and futures thinking. Using a qualitative approach and an action-research methodology, the work demonstrates how didactic innovations can transform classroom practices, strengthen pedagogical reflection, and foster the development of essential economic competencies in students.
Drawing on applied experiences in educational institutions across the northern subregion of Antioquia, this study provides valuable tools for teachers and scholars interested in linking economic education with a vision of sustainable and collective development. As such, it offers an essential contribution for those seeking to rethink the teaching of economics and to equip new generations with the skills needed to understand and shape a more prosperous future.PublishedEste libro presenta una investigación innovadora que analiza el proceso de enseñanza y aprendizaje de las ciencias económicas a partir de problemas socialmente relevantes y el pensamiento de futuro. A través de un enfoque cualitativo y una metodología de investigación-acción, el estudio evidencia cómo las innovaciones didácticas pueden transformar la enseñanza, fortalecer la reflexión pedagógica y desarrollar competencias económicas clave en los estudiantes.
Con experiencias aplicadas en instituciones educativas de la subregión del Norte de Antioquia, este estudio ofrece herramientas valiosas para docentes y académicos interesados en articular la educación económica con una visión de desarrollo sostenible y colectivo. De este modo, se ofrece una obra esencial para quienes buscan repensar la enseñanza y dotar a las nuevas generaciones de habilidades para comprender y construir un
futuro más próspero
Traiettorie riproduttive e mobilità tra Africa ed Europa
No full textPublishedSulla base di ricerche sul campo condotte in diversi contesti dell’Africa e in Italia, questa collettanea di saggi intreccia i dibattiti antropologici sulla parentela a quelli sulle migrazioni, esplorando la relazione tra mobilità transnazionale e traiettorie riproduttive di donne e uomini provenienti da vari contesti africani. Le politiche migratorie, le condizioni socioeconomiche, le aspettative sociali, i modelli di genitorialità, le appartenenze religiose, l’accesso al mercato del lavoro, le relazioni di genere e il capitale sociale che una famiglia è in grado di attivare sono tutti elementi che influenzano le traiettorie riproduttive, talvolta creando discrasie profonde tra il numero di figli avuti e quelli desiderati o tra forme di parentela e relazionalità estremamente differenti. Questi contributi ci mostrano l’estrema variabilità dei modelli, dei principi e delle condizioni che modellano le traiettorie riproduttive tanto in Africa quanto in Europa: una variabilità che, da un lato, impedisce di operare generalizzazioni essenzializzanti rispetto a qualsivoglia “comunità”, “diaspora” o “gruppo” preso in esame, ma che, dall’altro, consente di sottolineare similitudini profonde non solo tra persone provenienti da contesti africani diversi, ma anche tra questi e i cosiddetti “autoctoni”. Proprio perché influenzati dall’articolazione di molteplici fattori (socioeconomici, politici, abitativi, ideologici, religiosi, valoriali), i comportamenti riproduttivi risultano per loro natura plurali e sfaccettati, storicamente e culturalmente situati e non riducibili a visioni lineari, meccaniciste o essenzializzanti della vita sociale
Chapter L’architettura dell’inganno: studio prospettico e modellazione digitale della Cappella del Doge di Genova
No full textThe here collected contributions relating to the 46th International Conference of the Representation Disciplines Teachers, organized jointly by Sapienza University of Rome, Roma Tre University, and San Raffaele Roma University, aim to offer the scientific community a reflection on the theoretical and methodological aspects related to the concept of èkphrasis, a term that, in the field of representation, concerns descriptive, analogical, and digital activities that generate new knowledge in several areas of application. The Conference aims to place at the center of the discussion an interpretation of the concept of research that, without neglecting an idea of study, protection, and enhancement of environmental and cultural heritage, focuses on the needs of contemporary society and its possible developments, making use of innovative theoretical, methodological, and operational activities, including those characterized by an interdisciplinary approach. According to this interpretation, research can also be seen as a foreshadowing of the definition and testing of experimental proposals aimed at exploring new areas of investigation: this opens up imaginative and utopian perspectives in the relationship between the sciences, the arts, and the disciplines that contribute to common goals, through the experimentation of methods, techniques, and languages for conceiving, prefiguring, designing, and representing