bluuebunny/crossref_metadata_2025 huggingface dataset:
From Modernizing Tradition to Traditionalizing Modernity: U. R. Ananthamurthy's Samskara as Postcolonial Bildungsroman
Authors: Roy Arnab Dutta
Published: July 2024

The twentieth century is witness to a revival of interest in the bildungsroman as writers, especially from postcolonies in the Global South, turn to it to reflect on concerns of history, culture, and social life in a postcolonial setting. Scholars, however, disagree regarding the nature of these reworkings. Some see them as a continuation of the original European models established by Goethe, Dickens, and other European writers. Others find such associations Eurocentric and call for more local standards of evaluation. This article examines this debate by looking closely at a version of the postcolonial bildungsroman proposed by the Kannada writer U. R. Ananthamurthy in his 1965 novel Samskara. The novel follows an orthodox Brahmin priest from Karnataka who, disillusioned by the corruption and moral decay in his community, embarks on a pilgrimage to rediscover his identity in the rapidly modernizing world of twentieth-century India. Ananthamurthy's bildungsroman, while retaining some structural similarities, departs from European models in fundamental ways. The motif of the hero's journey, for instance, is flipped. The novel tracks the hero's growing discontentment with his community leading to a sense of communal alienation, thus inverting the European journey-trajectory that typically follows the hero's movement toward social integration. It also deviates from the generic Western rags-to-riches storyline that complements that hero's road to social integration. Instead, it adopts the narrative structure of the Niti-shastra, a set of precolonial Hindu texts that teach about the wise conduct of life. Such readings not only facilitate fresh ways of understanding the relationship between the Western and the postcolonial models, but they also allow new insights into understanding how South Asian authors utilize the bildungsroman to rediscover precolonial and classical works through modernity.
Heroines and Villains, Orphans and Thieves: The Motley Melodramas of Oliver Twist
Authors: D'Alessandro Michael
Published: July 2024

This essay examines Charles Dickens's incorporation of Georgian- and early Victorian-era theatrical melodrama into his 1837–39 novel Oliver Twist. It studies Dickens's text against genre theories of melodrama, Dickens's own staged readings of Twist, social histories of contemporaneous England, and highlights from the era's English melodramas (including The Castle Spectre and A String of Pearls; or, The Fiend of Fleet Street). Crucial to Twist's literary history was Dickens's engagement with a pervasive London theatrical culture, a move that both trained his readers and led to the book's enduring afterlife as a melodrama itself. The essay argues that Dickens utilizes consumers’ preconceived understandings of popular theatrical tropes to guide their expectations when reading Twist. Moreover, by tweaking recognizable melodrama tropes—altering genders, multiplying villainies—Dickens finally suggests that familial reconstruction and moral collectivity can counter society's ills.
Third World Studies
Authors: Okihiro Gary Y.
Published: July 2024

In this revised and expanded second edition of Third World Studies, Gary Y. Okihiro considers the methods and theories that might constitute the formation of Third World studies. Proposed in 1968 at San Francisco State College by the Third World Liberation Front but replaced by faculty and administrators with ethnic studies, Third World studies was over before it began. As opposed to ethnic studies, which Okihiro critiques for its liberalism and US-centrism, Third World studies begins with the colonized world and the anti-imperial, anticolonial, and antiracist projects located therein as described by W. E. B. Du Bois in 1900. Third World studies analyzes the locations and articulations of power around the axes of race, gender, sexuality, (dis)ability, class, and nation. In this new edition, Okihiro emphasizes the work of Third World intellectuals such as M. N. Roy, José Carlos Mariátegui, and Oliver Cromwell Cox; foregrounds the importance of Bandung and the Tricontinental; and adds discussions of eugenics, feminist epistemologies, and religion. With this work, Okihiro establishes Third World studies as a theoretical formation and a liberatory practice.
Novo desenvolvimentismo e desigualdades: notas sobre a visão de Bresser-Pereira
Authors: Felix Jorge
Published: July 2024

O conceito de desigualdade social é inerente ao ideário do desenvolvimento econômico, no entanto os autores clássicos dificilmente se referiam explicitamente ao tema. Essa ausência de citação confunde a percepção e provoca uma interpretação equivocada de que houve um menosprezo à distribuição de renda na elaboração da teoria desenvolvimentista. Bresser-Pereira, na construção do Novo Desenvolvimentismo, elabora e amplia a ênfase à desigualdade social. Este artigo expõe essa visão do autor e propõe uma linha de pesquisa com o objetivo de incorporar à teoria uma consistência para a formulação de políticas sociais compatíveis com o projeto novo-desenvolvimentista.
Critical and Strategic Metal Resources of Greece
Authors: Tsirambides Ananias , Filippidis Anestis
Published: July 2024

Greece has a large number of critical and strategic metal resources. The proven and indicated reserves of aluminum amount to 2.5 mt and their gross value €5.075 b. Those of chromium amount to 1.2 mt with gross value €4.320 b, while of cobalt are 129 th. t with gross value €3.348 b. The proven and indicated reserves of copper from Chalkidiki and Kilkis areas are approximately 3.04 mt and their gross value €24.776 b, while those of manganese are 2.25 mt with gross value €5.400 b. Molybdenum has been located in Pigi Kilkis with indicated reserves of about 7.7 th. t and gross value €326 m. Under mining are the vein type magnesite deposits of Gerakini Chalkidiki and North Evia. The total reserves (proven + indicated) of magnesite are 280 mt and their gross value €9.800 b. The most important lateritic Fe-Ni-bearing ores are those of Evia Island, Agios Ioannis Viotia, Lokrida Fthiotida, Mesopotamia and Ieropigi Kastoria. The proven and indicated reserves of nickel are 1.39 mt and their gross value €22.240 b. The Rizana/Lachanas porphyry-epithermal antimony deposit is considered the most important stibnite ore. The proven and indicated reserves of stibnite are at least 100 th. t with an average Sb content of 0.3 wt%. Copper, chromium, and cobalt present good prospects for mining. Platinum group metals (PGMs), with economic interest, are contained in the porphyry Cu deposits of Skouries Chalkidiki. Strymonikos Gulf, together with the neighboring coastal and submarine sands, is the most probable area for locating exploitable rare earth metals (REMs). There are excellent investment opportunities in the exploration and mining of Bi, Te, Ga, Ge, and In metals. The deposits of other critical and strategic metals of Greece should be adequately assessed.
Από τους castrati στους σύγχρονους κόντρα τενόρους
Authors: Σπανάτης Νίκος
Published: July 2024

Η διερεύνηση και σύγκριση της φωνής των castrati, των τραγουδιστών της πιο σκοτεινής σελίδας στη μουσική ιστορία, με την ηχητικά εγγύτερη σε αυτούς, σύγχρονη, ιδιότυπη και ανδρόγυνη φωνή των κόντρα τενόρων αποτελεί το πεδίο έρευνας της παρούσας διατριβής η οποία έχει στόχο την ερμηνεία της άριας da capo στις όπερες serie του Georg Friedrich Händel. Η έρευνα αφορά, επίσης, στη φυσιολογία των φωνών και στην ανατομία του σώματος, στις διαφορές της αντήχησης και στον μηχανισμό παραγωγής του ήχου, στη λειτουργία της αναπνοής, στην ιστορική καταγραφή των registri, στην ανάλυση και αποσαφήνιση του falsetto και της κεφαλικής φωνής, καθώς και στη μοναδική ιστορική ηχογράφηση του τελευταίου castrato Alessandro Moreschi. Ο castrato Francesco Bernardi Senesino ως πρωταγωνιστής (Primo Uomo) στις δέκα οκτώ πιο γνωστές όπερες του Händel, απέκτησε φήμη με τις αριστοτεχνικά ερμηνευτικές υπερβάσεις και εκπληκτικές του ερμηνείες, αναδεικνύοντας, μεταξύ άλλων, το κίνητρο του συνθέτη να προκαλέσει συναισθήματα στο κοινό, πάθη και βαθειά συγκίνηση. Διερευνάται, επίσης, η ιστορική διαδρομή που συνδέει τον Senesino, με τα χειρόγραφα στολίδια που κατέγραψε ο Domenico Corri, μέσω του Nicola Porpora και αντλούνται πληροφορίες από σχετικές πηγές της εποχής για την ερμηνεία των αριών. Ο συγγραφέας, ως σύγχρονος κόντρα τενόρος, ερμηνεύει με όργανα εποχής, τις δέκα πιο γνωστές άριες da capo, από πέντε όπερες που συνέθεσε ο Händel για τον Senesino, προσθέτοντας στολισμό σε αυτές, μετά από μελέτη θεωρητικών συγγραμμάτων της εποχής και από έρευνα στα σημειωμένα στολίδια του συνθέτη, αποδίδοντας μια εμπεριστατωμένη απόδοση της φωνητικής γραφής του Händel.
Scalable indexing and query processing of big spatio-temporal data
Authors: Κουτρουμάνης Νικόλαος
Published: July 2024

Η εποχή μας χαρακτηρίζεται ως η «Εποχή των Μεγάλων Δεδομένων» όπου ο όγκος των παραγόμενων δεδομένων αυξάνεται εκθετικά. Πολλά από τα παραγόμενα δεδομένα καταγράφουν πληροφορίες γεγονότων και φαινομένων που εκτυλίσσονται τόσο στο χώρο όσο και στο χρόνο. Αυτού του είδους τα δεδομένα είναι επίσης γνωστά ως χωροχρονικά δεδομένα, τα οποία συναντώνται σε διάφορους τομείς όπως ο πολεοδομικός σχεδιασμός, η υλικοτεχνική υποστήριξη μεταφορών, η επιδημιολογία και η παρακολούθηση του περιβάλλοντος. Η ανάλυση αυτών των δεδομένων σε μεγάλη κλίμακα, μπορεί να αποκαλύψει μοτίβα και τάσεις από τις οποίες μπορεί να εξαχθεί πολύτιμη γνώση. Παρόλο που οι παραδοσιακές προσεγγίσεις διαχείρισης δεδομένων έχουν μελετηθεί εκτενώς, εξακολουθεί να αποτελεί πρόκληση η υποστήριξη αποτελεσματικών λειτουργιών σε περιβάλλοντα υψηλής κλιμακωσιμότητας. Η χρήση νέων συστημάτων διαχείρισης δεδομένων και αλγορίθμων σε κατανεμημένα περιβάλλοντα είναι απαραίτητη για την κάλυψη των απαιτήσεων μεγάλων όγκων δεδομένων. Προς αυτή την κατεύθυνση, η παρούσα διατριβή εστιάζει στους θεματικούς τομείς διαχείρισης δεδομένων όπως: i) της αποθήκευσης, ii) της ευρετηρίασης, iii) των επερωτήσεων και iv) της επεξεργασίας μεγάλων χωροχρονικών δεδομένων. Οι προτεινόμενες μέθοδοι και αλγόριθμοι βελτιώνουν την εφαρμογή ευρέως χρησιμοποιούμενων τρόπων αποθήκευσης και πλαισίων του οικοσυστήματος των μεγάλων δεδομένων για χωροχρονικά δεδομένα, τα οποία δεν υποστηρίζουν εγγενώς. Οι προτεινόμενες λύσεις μπορούν να κλιμακωθούν αποτελεσματικά, καθιστώντας τις κατάλληλες για περιπτώσεις δεδομένων υψηλής εντάσεως.
Mathematical structure of fuzzy connectives with applications in Artificial Intelligence
Authors: Καραμπίνης Ιωάννης
Published: July 2024

Ένα από τα πιο περίπλοκα και σημαντικά προβλήματα που αντιμετωπίζουν οι σύγχρονες κοινωνίες αποτελεί η εκτίμηση της διακινδύνευσης των κατασκευών έναντι φυσικών ή ανθρωπογενών κινδύνων. Το πρόβλημα αυτό μπορεί να περιγραφεί σε φυσική γλώσσα, ωστόσο η αυστηρή μαθηματική του διατύπωση είναι δύσκολη λόγω της εγγενούς ασάφειας και αβεβαιόοτητας που αφορά τόσο το μέγεθος του κινδύνου, όσο και της πιθανής του επίπτωσης. Έτσι, για την αντιμετώπιση παρόμοιων προβλημάτων, είναι αναγκαία η χρήση διαφορετικών μαθηματικών εργαλείων.Ένα τέτοιο εργαλείο αποτελεί η Ασαφής Λογική. Η μεθοδολογία αυτή ενσωματώνει με φυσικό τρόπο την ασάφεια στις υποκείμενες μαθηματικές εξισώσεις. Από την άλλη, ένα διαφορετικό εργαλείο δίνεται από την Τεχνητή Νοημοσύνη και την Μηχανική Μάθηση. Στον πυρήνα της, η Μηχανική Μάθηση χρησιμοποιεί αυστηρά μαθηματικά εργαλεία για να μάθει από ένα σετ δεδομένων, χωρίς να επιβάλλονται περιορισμοί στην μορφή του μοντέλου.Στο πλαίσιο της παρούσας Διατριβής, διερευνήθηκε η θεωρία των δύο αυτών διαφορετικών προσεγγίσεων και εξετάσθηκε πως κάθε μία από αυτές αντιμετωπίζει την ασάφεια απο διαφορετική σκοπιά. Επίσης, αναπτύχθηκαν καινοτόμα εργαλεία που αντιμετωπίζουν το πρόβλημα της εκτίμησης της σεισμικής διακινδύνευσης των κατασκευών, τόσο από την σκοπιά των παραμορφώσιμων όσο και των απαραμόρφωτων σωμάτων. Επιπρόσθετα, εξετάσθηκαν με λεπτομέρεια οι ασαφείς σύνδεσμοι που παίζουν κεντρικό ρόλο σε ένα ευφυές πληροφοριακό σύστημα λήψης αποφάσεων που συνδυάζει ασαφή λογική και μηχανική μάθηση. Αναπτύχθηκαν καινοτόμα θεωρητικά αποτελέσματα στον τομέα αυτό και διερευνήθηκε πώς αυτά μπορούν να ενσωματωθούν σε ένα ευφυές σύστημα λήψης αποφάσεων.
Load torque observation and compensation for permanent magnet synchronous motor based on sliding mode observer
Authors: Lu Zenghui , Fan Hongjie , Xu Dong
Published: July 2024

Background Permanent magnet synchronous motors (PMSM) are widely used in various industries. However, in practical applications, the time-varying nature of load torque may lead to speed fluctuations, negatively impacting the motor's control performance and stability. To mitigate these issues, this paper proposes a load torque observation method for PMSMs based on a sliding mode observer. Methods The sliding mode observer is designed to estimate the load torque and convert it into a current, which is fed back as a feedforward compensation to the q-axis current in the current closed-loop control system. The observer's dynamic performance is optimized using a genetic algorithm to minimize the Integral of Time-weighted Absolute Error (ITAE) between the observer and the actual system state. Experimental tests are conducted on a motor torque testing platform. After stabilizing the motor at 800rpm, a sudden torque of 0.5Nm is applied. Results Compared to the situation without load torque compensation, the motor speed fluctuations are reduced by approximately 60% after adding load torque compensation. Conclusions This enhancement improves the system's speed control performance during torque variations and increases the system's robustness and disturbance rejection capability.
Mastering Technologies for Working with Big Data As an Element of Modern Training of University Humanities Students
Authors: Shutikova M. , Beshenkov Sergey
Published: July 2024

g Data is a qualitatively new information object that requires special methods of analysis and processing. The peculiarity of Big Data is the following: traditional methods of data processing in the case of Big Data may not be effective, since they require very large time frames and computing resources; Big Data, in many ways, loses its discrete structure and approaches its properties to structures of continuity, which complicates the use of traditional methods of discrete analysis.

The article discusses approaches to the study of Big Data in humanitarian universities.

The sources of the emergence of big data in this area are discussed as an imbalance between the syntactic and semantic aspects of the information object. It is substantiated that in humanitarian universities it is advisable to place emphasis on mastering the modeling methodology, which, in many respects, allows eliminating this imbalance.
Mathematical, Reading, and Natural Science Literacy in Primary School: Interconnection, Continuity, Integration
Authors: Kopachevskaya L.
Published: July 2024

The article is devoted to the problem of developing functional literacy in primary school students. The results of a comparative analysis of the formed and tested types of activities of the basic components of functional literacy (Reading, Mathematics, Science) are presented. Identical and specific types of activities are identified. Using the example of the results of completing tasks of meta-subject regional diagnostic work by schoolchildren in the Moscow region, the existence of a problem of transferring identical competencies from one type of literacy to others was demonstrated. A solution to this problem has been proposed. The article is addressed to teachers implementing federal educational programs of basic general education, regional coordinators of the project «Monitoring the formation of functional literacy of students».
The influence of modern methods of processing and sterilization on the quality of fruit and vegetable raw materials and juice products
Authors: BURAK LEANID
Published: July 2024

The monograph is a scientific review and critical analysis of the acceptability and effectiveness of various new methods of disinfection of plant materials, the impact of modern physical and chemical processing methods on the quality and microbial safety of fruits and vegetables. The paper presents a critical scientific review of the application of thermal and non-thermal technologies in the field of juice processing over the past 10 years. A comprehensive analysis of the operating principle and influence of various technologies on the inactivation of microorganisms and enzymes, nutritional and functional characteristics, physicochemical and organoleptic properties of a wide range of juice products is given. The application of various combinations of barrier technologies in the field of sterilization is also discussed in detail, the advantages, limitations, and current prospects for the use of various sterilization technologies are summarized. The monograph is intended for a wide range of readers: researchers, graduate students, undergraduates, teachers of higher educational institutions, sanitary doctors, food industry engineers, technologists, chemists, microbiologists.
How should we treat postherpetic neuralgia?
Authors: Czerwik Julia , Cieszkowska Joanna , Dmochowska Joanna , Czubala Marta , Wróblewski Wiktor
Published: July 2024

Postherpetic neuralgia (PHN) is the most common long-term complication of varicella-zoster virus (VZV) reactivation. It is characterized primarily by persistent pain more than 90 days after the illness at the site where the rash was. This pain is sharp, burning, stabbing in nature. Postherpetic neuralgia can lead to a reduced quality of life and negatively affect sleep and daily functioning. The first line of treatment is currently conservative methods, which include anticonvulsants, antidepressants, topical lidocaine, as well as opioids and topical capsaicin. If these measures are ineffective, individually tailored interventional methods may be necessary. Among these, botulinum toxin A injection is the most common. Other methods focus on neuromodulation (which is the alteration of nerve activity through targeted delivery of a stimulus) or blocking individual elements of the nervous system.
Transapical off-pump implantation of artificial mitral neochords in a patient after Bentall procedure - case report
Authors: Bocianiak Bogumił , Krzemińska Paulina , Kranc Kacper , Munzberger Dominika , Ruta Damian , Hamerska Laura , Hamerska Julia , Antczak Joanna , Lipska Julia , Fenrych Urszula , Wojtczak Karolina , Skupińska Olga , Kajka Anna
Published: July 2024

The NeoChord DS 1000 system offers a minimally invasive alternative for treating degenerative mitral regurgitation (MR), particularly in high-risk patients with previous aortic surgery. A 74-year-old male with a history of Bentall procedure presented with severe MR and dyspnea (NYHA III). Transapical mitral valve repair was performed using the NeoChord DS 1000 system. Three artificial chordae were implanted, significantly reducing MR. The patient had an uneventful recovery and was discharged in good condition after 8 days.
This case demonstrates the NeoChord system's potential in high-risk patients where traditional MVR poses high risks. Transapical access avoids sternotomy and extracorporeal circulation, offering a safer alternative. The NeoChord DS 1000 system shows promise for high-risk patients and those with complex surgical histories, though further research is needed to confirm its long-term efficacy and durability.
https://alojaservicios.us.es/difuseditorial/Extra_content/orc_ps_24/orc_editorial_110.pdf
Authors: Petrollese Mario , Cau Giorgio , Marchionni Matteo , Lorenzo Marroccu Marcello , Merchán Rosa
Published: July 2024

Pumped Thermal Energy Storage (PTES) is a promising technology for the long-term storage of electrical energy by using thermal energy reservoirs. PTES can be mainly classified into system configuration employing Joule-Brayton cycles and systems using Rankine cycles. With respect to Rankine cycles, the coupling between a high-temperature heat pump with an ORC power system is attracting increasing interest. In this framework, an experimental Rankine PTES system based on the coupling between a kW-scale ORC system with a high temperature heat pump is going to be developed and commissioned. In this paper, the procedure followed for the design of such experimental facility is presented and discussed. Four main configurations are proposed and compared in terms of achievable system roundtrip efficiency and minimization of the exergy destruction rate. Results demonstrate that roundtrip efficiencies lower than 40% are reached with the use of out-of-shelf devices, while by a proper system configuration and the customized design of the heat engine and heat pump, roundtrip efficiencies higher than 60% can be achieved.
SMALL-SCALE TURBOPUMPS FOR WASTE HEAT RECOVERY APPLICATIONS BASED ON AN ORGANIC RANKINE CYCLE, MODELING, ANALYTICAL AND EXPERIMENTAL INVESTIGATIONS.
Authors: Zakeralhoseini Sajjad , Schiffmann Jürg
Published: July 2024

The organic Rankine cycle (ORC) system is considered a promising technology to exploit thermodynamic potential of waste heat. The weight and size of standard pumps can penalize the benefits of installing an ORC system on vehicles. Small-scale ORC applications would greatly benefit from more compact and efficient pumps. This paper presents the results of numerical and experimental analyses of small-scale turbopumps for ORC systems. A parameterized design tool is developed, allowing the rapid generation of numerous turbopump geometries and their fluid domains. The design tool creates a dataset of numerous turbopumps with different geometrical parameters. The turbopumps are investigated with CFD analysis, and the accomplished results are analyzed to characterize the influence of tip clearance and splitter blades on the performance (slip factor and head rise) of small-scale ORC turbopumps. The numerical results are employed to infer dimensionless maps (specific speed-specific diameter) and 1D models, which enable the capturing of the influence of down-scaling in the early design process of such machines. In the next step, two turbopumps are designed using the new design tool and then tested experimentally to validate the numerical procedure. The good agreement between experimental performance characteristics and developed models validates the computational results and reduced-order models. Following the experimental validation, the performance of an ORC system designed for the waste heat recovery of truck engines is estimated using the performance characteristics of the experimental turbopumps instead of a commercial multi-stage centrifugal pump. The developed turbopumps are one order of magnitude more compact compared to commercial systems. Further, the comparison suggests that the designed turbopumps improve the targeted ORC’s thermal efficiency by 0.51% and reduce its back-work ratio by 42% and 67%. Keywords: small-scale turbopump, organic Rankine cycle, computational fluid dynamics, experimental investigation, pre-design diagrams, 1D models
TES4TRIG: DEVELOPMENT OF A DEMONSTRATOR FOR THE PRODUCTION OF ELECTRICITY, HEATING AND COOLING BASED ON AN ORGANIC RANKINE CYCLE AND AN EJECTOR COOLING CYCLE DRIVEN BY HIGH-TEMPERATURE PARABOLIC TROUGH COLLECTORS WITH THERMAL ENERGY STORAGE
Authors: Braimakis Konstantinos , Tziritas Dimitrios , Stavrakakis George Μ. , Terrón Gutiérrez Julio , Dutta Siddharth , Xynos Christos , Zervas Panagiotis , Karellas Sotirios
Published: July 2024

This study presents the development of the TES4Trig demonstrator that will be installed for covering the energy needs of the Administration building of the Lavrio Technological and Cultural Park (LTCP) in Attica, Greece within TES4Trig CSP-ERANET project. The system is driven by high-temperature parabolic trough collectors (PTC) coupled with innovative solid-state thermal energy storage (TES). Heat is supplied to an Organic Rankine Cycle (ORC) – Ejector cooling cycle (ECC) through a heat transfer fluid (HTF). The ORC-ECC is capable of the following operating modes: 1) electricity-only, 2) combined heat and power (CHP) and 3) cooling. The system energy production and consumer demand were considered for the conceptual design and preliminary definition of the operating strategies of the ORC-ECC. The final design of the ORC-ECC system is based on the use of R1233zd(E) as a working fluid, operating at a maximum temperature of 140℃.
Toward a Green Energy Community: Integration of micro-ORCs combined with renewable energy technologies in buildings
Authors: Rodríguez-Pastor Diego Antonio , Soltero Sánchez Víctor Manuel , Carvajal Trujillo Elisa , Becerra José Antonio , Chacartegui Ricardo
Published: July 2024

Distributed microgeneration is an alternative for aggregate energy integration into the electricity grid. Low-temperature heat recovery systems, such as ORCs, are particularly interesting given their compactness and safety for application in the residential sector, operating at moderate pressures and low heat source temperatures. Energy surpluses generated by renewable technologies commonly used in the building sector, such as photovoltaics or micro-wind, can be used to power systems that provide backup and add inertia to the grid. In this study, micro-ORCs (< 2 kWe) were integrated with different heat supply technologies in buildings, including storage with DHW water tanks or sensible heat in bedrock for heating. An overview of possible configurations and techno-economic optimization is provided, offering combined strategies with other installations and additional characterization of energy communities with a larger number of connected neighbors, determining optimized integrations for covering thermal and electrical demands.
OPTIMUM COUPLING OF THERMAL ENERGY STORAGE AND POWER CYCLES FOR CARNOT BATTERIES
Authors: Guccione Salvatore , Guedez Rafael
Published: July 2024

To enable the widespread exploitation of intermittent, low-cost, and non-dispatchable renewable energy technologies, energy storage plays a key role in providing the required flexibility. In the spectrum of energy storage systems, one out of a few geographically independent possibilities is the storage of electricity into heat, so-called Carnot batteries. For thermal-to-electricity reconversion, depending on the operating energy storage temperatures, conventional or advanced power cycles can be integrated into the system, yielding different techno-economic performances. This work proposes a methodology that enables decision-making in selecting the adequate power cycle and Thermal Energy Storage (TES) type for a wide range of operating temperatures between 200 and 800 °C. To select the optimum coupling of TES and power block, a techno-economic optimization has been conducted aimed at minimizing the Levelized Cost of Storage (LCOS) for different plant capacities and charging costs. The study explores various power block configurations, including Organic Rankine Cycle (ORC), steam Rankine cycle, and supercritical CO2 (sCO2) Brayton cycle. Additionally, it evaluates different TES options such as molten salt, particle, and air packed bed TES. Results highlight that, for a charging cost of 50 EUR/MWh, the most cost-effective combination of TES and power block involves sCO2 power blocks with recompression and intercooling, along with particle-based TES operating at temperatures between 600 to 800 °C and a temperature difference of 200 °C. ORCs are suitable for low temperatures (up to 350 °C) and high temperature differences, while the steam Rankine cycle is considered optimal between the low-temperature and the sCO2 preferred regions. Air-packed bed TES is suggested as a viable option when TES represents a large share of the capital cost, with low charging costs, low hot temperatures, or low temperature differences. Molten salt TES is ideal when its design temperatures align with the operating limitations of the salts. Particle-based TES is the most cost-effective choice across a wide range of temperatures, at small (10 MW) and large scales (100 and 200 MW).
Robust and Fast Meanline Methodology for Radial Inflow Turbines with Non-ideal Gases for System Level Optimisation of Organic Rankine Cycl
Authors: Freytag Carola , Alvarez-Regueiro Eva , Ale Martos Pablo , Barrera-Medrano Esperanza
Published: July 2024

Waste heat recovery aims to increase the overall system efficiency and thus, reduce emissions. One technology commonly considered is the Organic Rankine Cycle (ORC) which uses a refrigerant as the working fluid. For an efficient operation of the ORC, the different components, e.g., the turbine, need to be optimised considering the entire system. This paper investigates the capability of meanline modelling for nozzled turbines to model the non-ideal gas effects of different refrigerants. For optimal implementation at a system level, it is important to have sufficient accuracy and low computational cost. The meanline model was compared with CFD for three different working fluids. A 3D parametric model was generated, and a numerical experiment was performed using Latin Hypercube Sampling. Seven meanline design parameters were investigated over a broad design space to show the influence of each respective one on turbine performance. Subsequently, the meanline model was calibrated against a subset of geometries and compared to the entire data sample. The average error stayed below 5%, which is sufficiently accurate for preliminary-stage calculations.
Investigation of the turbulence level and the vortex shedding in a turbine cascade working with an organic vapor at subsonic Mach numbers
Authors: Hake Leander , hanndermeier SuStep , aus der Wiesche Stefan , Matar Camille , Cinnella Paola , Gloerfelt Xavier
Published: July 2024

Detailed turbulence and trailing edge vortex shedding measurements employing hot-wire anemometry and numerical simulations using a high-resolution unsteady Reynolds-averaged Navier-Stokes method were conducted for the high subsonic flow of the organic vapor Novec 649 through the VKI turbine cascade at elevated pressure and temperature level. Turbulent spectra downstream and upstream of the cascade were obtained and analyzed. The simulations indicated that acoustics waves (shed shockwaves) and locally supersonic flow occurred at the trailing edge even at a moderate isentropic exit Mach number of 0.7. Strong evidence for that loss-relevant mechanism was found in the hot-wire signals. The vortex shedding frequency depended primarily on the Reynolds number, not the Mach number.
EVALUATION OF THE PERFORMANCE OF MULTIPLE SUPERCRITICAL CO2 POWER CYCLES IN WASTE HEAT RECOVERY APPLICATIONS
Authors: Chibli Hicham A. , Read Matthew , Sayma Abdulnaser
Published: July 2024

This paper aims to systematically evaluate the common supercritical carbon dioxide power cycles that are suitable for low to high grade waste heat recovery applications, with source temperatures ranging from 450 to 850 °C. A number of cycles varying from the simple to the fully cascaded split cycles are investigated against a predefined waste heat source for multiple temperatures and flow rates with a target power net yield of the order of 1 MWe. The conditions at the inlet to the main compressor in the sCO2 loop are also varied to quantify the role of the environmental heat sink in effective heat recovery. The sCO2 cycle parameters including the mass flowrate and split ratio as well as the effectiveness of the individual heat exchangers are optimized for multiple pressure ratios. Additionally, a detailed exergy analysis is conducted to identify the sources of entropy generation in the various components and enable a detailed comparison of the various cycle configurations reviewed. Improving the quality of the heat source from 450 to 850 °C yielded ~30% increase in cycle performance, while degrading the heat sink quality from 15 to 35 °C reduced the net output power by ~30%. The cascaded and split cycles were determined to achieve the highest performance across all conditions considered.
INFLUENCE OF DOPANT FLUORINATION ON THE HEAT TRANSFER BEHAVIOUR OF CO2-BASED MIXTURES IN TRANSCRITICAL POWER CYCLES
Authors: Doninelli Michele , Di Marcoberardino Gioele , Invernizzi, Costante Mario , Giulio Iora Paolo
Published: July 2024

CO2-based mixtures are recognized to be an effective working fluid to overcome the limitations of pure sCO2 cycles for power production in high-temperature environments. Based on the temperature level of the heat source, several dopants, characterized by high critical temperature, can be adopted for blending CO2. As thermal stability is one of main concern in the working fluids selection, fluorinated compounds have been considered in the recent years as potential solution due to high C-F chemical bond energy. However, the available thermodynamic and transport properties of CO2 mixtures with fluorinated hydrocarbons are relatively scarce, thus further experimental and theoretical investigations are necessary to properly design the power cycle components. The CO2-based mixtures are considered in this work for high-temperature heat recovery to assess the influence of fluorine atoms substitution to hydrogen atoms both on cycle efficiency and heat exchangers size. Benzene (C6H6) and two fluorinated derivatives (fluorobenzene C6H5F, hexafluorobenzene C6F6) are considered here to assess the influence of the presence of fluorine atoms in the molecule of the dopant on the transport properties of the CO2-mixtures and their heat transfer behaviour. These three halogenated aromatic dopants possess good thermal stability related with the benzene ring structure and could be potentially exploited for medium-high temperature level applications (350-550°C) such as waste heat recovery and concentrated solar power. Specific models for transport properties implemented in Matlab codes are optimized for the considered mixtures with a novel approach, and the design of the PCHE recuperator has been carried out. It turns out that the use of fluorobenzene as CO2 dopant in medium-high temperature heat recovery can be a good solution in terms of heat exchangers sizes, efficiency, cost, and environmental characteristics (GWP and toxicity).
Numerical Analysis of Aerodynamics and Performance of a Radial-Inflow Micro-ORC Turbine
Authors: Ardaneh Fatemeh , Zocca Marta , Uusitalo Antti , Turunen-Saaresti Teemu
Published: July 2024

Organic Rankine Cycle (ORC) has proven to be an effective way to recover waste heat. The performance of ORC systems is profoundly affected by turbine selection, which is one of the most critical components. In this study, a numerical aerodynamic analysis of a micro-ORC turbine is carried out as an effort towards the formulation of a reduced order model (ROM) of the turbine for the dynamic simulation of the complete ORC system. The studied turbine is the radial-inflow turbine of the waste heat recovery micro-ORC test rig at the Laboratory of Fluid Dynamics, LUT University. The performance of the turbine, which features a highly supersonic flow at the stator outlet, is evaluated through steady-state CFD simulations of the complete turbine geometry using linear siloxane MDM (Octamethyltrisiloxane C8H24O2Si3) as working fluid. Results are discussed and compared with experimental data. Turbine efficiency is studied numerically at varying rotational speeds (25000-31000 rpm). A significant fluctuation in the flow angle at the stator is observed at low rotational speeds, while it decreases at higher speeds. At increasing rotational speed, the analysis shows a corresponding increase in the discharged flow rate, and the turbine efficiency up to 0.2061 kg/s and 79.3, respectively. Moreover, the flow features through the turbine nozzle ring and rotor blades are examined and discussed for selected operating conditions
Experimental Investigation of a Small-Scale Reversible High- Temperature Heat Pump – Organic Rankine Cycle System for Industrial Waste Heat Recovery
Authors: Velanparambil Ravindran Rahul , Cotter1 Donal , Wilson Christopher , Jun Huang Ming , Hewitt Neil
Published: July 2024

A reversible system that can function as both a high-temperature heat pump (HTHP) and an organic Rankine cycle system (ORC) can enhance the efficiency of industrial waste heat recovery. The reversible system can either upgrade waste heat to process heat (HTHP mode) or generate power (ORC mode). This paper presents the experimental investigation of a small-scale reversible HTHP-ORC system using an automotive open-drive scroll machine to operate as the compressor (HTHP) and expander (ORC) in the system. The refrigerant R1233zd(E) was selected as the working fluid for both modes of operation. Based on an analysis of the experimental results, the HTHP achieved a COPel of 4.6 at 30 K temperature lift, with the scroll compressor achieving a maximum overall isentropic efficiency of 73.4%. In ORC mode, at a source temperature of 75 °C, the cycle thermal efficiency was 3.8%, and the expander overall isentropic efficiency was 43%.
STUDYING CARBON DIOXIDE AND ACETONE MIXTURES IN A SINGLE-STAGE ABSORPTION-COMPRESSION CYCLE FOR HEATING AND COOLING APPLICATIONS
Authors: Gómez-Hernández Jesús , Kholghi Alhi , de Vega Mercedes , Villa Briongos Javier , Grimes Ronan
Published: July 2024

This communication analyzes the performance of a zeotropic fluid, composed by the mixture of carbon dioxide and acetone, in a vapor compression cycle with a solution circuit. The working fluid is characterized by a high temperature glide that depends on the mixture composition. The high critical temperature of the acetone and the good thermal properties of carbon dioxide makes this mixture a promising heat transfer fluid for industrial heat pumps that need to supply energy for heating and cooling processes. The heat pump analyzed has these components: evaporator, compressor, condenser, two internal heat exchangers and an expansion valve. In addition, a second liquid line with a solution pump is used to circulate the liquid from the gas-liquid separator to an internal heat exchanger, and then, to the condenser. In this way, the gas-liquid separator allows the fluid to leave the evaporator as a vapor-liquid mixture. This heat pump configuration working with the CO2/acetone mixture could provide the energy needs of an industry that requires both heating and cooling. Depending on the binary mixture composition, the source and sink temperatures change as well as the coefficient of performance. For instance, an 55% CO2/45% acetone in mass fraction, can provide heat to the sink at an average thermodynamic temperature of 110ºC, and refrigeration at an average thermodynamic temperature of 0ºC, showing a total COP of 2.55. This configuration would work at a high pressure of 40 bar and a low pressure of 10 bar.
VALORISING THERMAL RECYCLING PROCESSES OF FIBREREINFORCED COMPOSITES USING ORGANIC RANKINE CYCLES FOR COMBINED HEAT AND POWER APPLICATIONS
Authors: Moradi Ramin ,   *,, Yang Liu
Published: July 2024

Recycling is one of the most challenging issues in many different sectors, which can bring both significant economic and environmental benefits. Hence, recycling is one of the few domains in that economic interests are in line with diminishing environmental concerns. Among the feasible and profitable recyclable materials, fibre-reinforced polymers (FRPs) are at the early stages of technology readiness with end-of-life FRP material projected to increase significantly in the coming years. Therefore, the economic and environmental impacts of FRP recycling plants should be investigated to develop a reliable business case to support the development of a circular economy for these materials. To this end, the recycling process should be robustly designed, optimised, and integrated with energy systems to maximise economic and energy-saving benefits. In this work, an FRP thermal recycling plant coupled with a 30 kWel/175 kWth organic Rankine cycle (ORC) system for combined heat and power (CHP) is studied. The environmental benefits of this integrated recycling-energy system are presented in terms of net CO2 and operational costs. Results show that the integration with at least 50 residential apartments can significantly improve the economic and environmental indicators compared to the separate recycling plant and buildings being supplied by the electricity and natural gas (NG) grids. These indicators are identified by comparing the direct and indirect CO2 emission and operational costs of the recycling plant coupled with the ORC-CHP system with those generated by stand-alone systems producing virgin fibres, supplying domestic electric demand using the electric grid, and domestic space heating using the NG grid.
EXERGY-BASED METHODS FOR HEAT PUMPS
Authors: Hofmann Mathias ,   1,*,  2,3,  2,3,  1, 4,  1, Freißmann Jonas , Fritz Malte , H. Alexe Jeremias , Witte Francesco , Tsatsaronis George
Published: July 2024

Heat pumps are undoubtedly a relevant technology option for decarbonizing the residential sector’s heating supply and providing process steam in the industry. Nevertheless, thermodynamic analysis and evaluation of heat pumps needs to be more accurate. Exergy analysis provides a method that detects the real thermodynamic inefficiencies of the components and the overall process. Determining the exergetic efficiency also provides a statement about the process quality and the maximum possible potential for process optimization. In addition, heat pump concepts with different inputs (compression heat pumps, absorption heat pumps) can be consistently compared with each other. The exergoeconomic analysis enables the identification of the cost-generation process and the determination of the heat production costs. Thermal Engineering Systems in Python (TESPy) is a free and open-source software for the simulation and analysis of energy conversion systems like gas turbines, steam power plants, heat pumps, or refrigerators. Exergy balances are solved in postprocessing for all predefined components, and exergetic efficiencies are determined. Simulation results and comparative exergy analyses are presented for different heat pump concepts. The paper is intended to establish the exergy-based methods for heat pump analysis. The results show which concepts and components are suitable for providing indoor heat and process steam from renewable energy sources.
Analytical estimation of the presence of non-condensable gases in the condensate tank of an Organic Rankine Cycle
Authors: Dhanasegaran Radheesh , Uusitalo Antti , Honkatukia Juha , Turunen-Saaresti Teemu
Published: July 2024

The presence of non-condensable gases (NCGs) can have a negative impact on the ORC performance due to the reduced expansion ratio over the expander. The presence of NCGs can reduce the turbine expansion ratio significantly, especially in such systems in where siloxanes or high molecular weight hydrocarbons are used, requiring condensing pressures well below the atmospheric pressure. The ORC facility that uses siloxane MDM as the working fluid at LUT University has been considered in the present study. Experimental and simulation data of the facility from the previously published studies suggest that defining the working fluid state in the condenser and condensate tank suffers from significant uncertainty due to the existence of NCGs. Therefore, an attempt has been made to analytically estimate the quantities of NCGs present in the condensate tank of the ORC system using 1-D calculations based on ideal gas assumptions. It was assumed, that air is the NCG that is present inside the condensate tank for simplifications. Since the compressibility factor of MDM vapor is close to 1 at such low condensing temperatures, its behavior is close to ideal gas and hence, the assumption of ideal conditions seems viable. Data from three different experimental measurements with varying temperatures have been tested using the proposed analytical method and the corresponding quantities of the MDMair mixture during the system operation have been estimated. The results showed that the presence of the NCG was dominant, especially in the case of measurement data with lower temperatures, and was reduced for higher condensate tank temperatures.
Tożsamości Półwyspu Iberyjskiego w perspektywie artystycznej
Authors: Golemo Karolina , Romanowska Jadwiga
Published: July 2024

Brak abstraktu dla tego artykułu.
Andaluzyjska convivencia
Authors: Iwanowicz Ada
Published: July 2024

ANDALUSIAN CONVIVENCIA: INTERCULTURAL RELATIONS IN MEDIEVAL ANDALUSIA IN SELECTED HISTORICAL NOVELS
The article aims to demonstrate that scientific concepts related to convivencia are present in historical novels about Andalusia. Although research on this topic is popular, it has not gained much attention in Poland. This study analyzes and compares the theories of Américo Castro, Claudio Sánchez-Albornoz, Évariste Lévi-Provençal, Thomas Glick and Oriol Pi Sunyer, María Rosa Menocal, and Brian Catlos with the portrayal of Andalusia in the following novels: The Scarlet Manuscript by Antonio Gala, The Hand of Fatima by Ildefonso Falcones, Ivory Elephant by Nerea Riesco, and The Muse by Jessie Burton. Furthermore, it explores the impact of medieval Andalusia’s culture and history on Spanish identity.
Preserving the vital pulp in the permanent dentition: a simplified guide to indirect pulp capping
Authors: Gupta Disha , Howell William , Iqbal Shumaila , Camilleri Josette
Published: July 2024

This article discusses vital pulp therapy in the adult dentition and describes two cases where a different strategy for caries removal has been used followed by dressing with a contemporary material and tooth restoration on the same visit. A simplified guide for best practice is given.

CPD/Clinical Relevance:

Vital pulp therapy is an important procedure that requires clinical skill and can be undertaken in general practice.
An apically positioned flap and free gingival graft around an implant
Authors: Morris Matthew K , Matthews Debora , Price Richard Bengt
Published: July 2024

Following the ‘2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions,’ hard and soft tissue deficiencies have been debated in the literature with keratinized mucosa at the forefront. In this case report, the present author investigated whether an apically positioned flap and free gingival graft to increase keratinized mucosa and vestibular depth improved oral hygiene and patient comfort around an implant-retained upper complete denture. Using an apically positioned flap in combination with free gingival graft to augment the soft tissues around implants with hard and soft tissue deficiencies, increased both the keratinized mucosa and vestibular depth to correct the soft tissue deficiencies. This case report highlights the importance keratinized mucosa and vestibular depth has at the patient and site level in improving oral hygiene and patient comfort. This case report also supports the growing evidence that the ideal periodontal phenotype around implants is to have keratinized mucosa ≥2 mm and vestibular depth ≥4 mm.

CPD/Clinical Relevance:

This case report supports growing evidence that the ideal periodontal phenotype around implants is to have keratinized mucosa ≥2 mm and vestibular depth ≥4 mm.
Injury under the influence: A case report
Authors: Darwood Allegra NR , Dawood Andrew JS
Published: July 2024

A detailed and honest social history is vital when piecing together any clinical diagnostic puzzle. This case presentation highlights this, leading to a surprising diagnosis for both patient and clinician. Additionally, access to cone beam computed tomography (CBCT) has vastly widened diagnostic accuracy within the dental field, and this case emphasizes the importance of thorough training to identify, and interpret, incidental findings.

CPD/Clinical Relevance:

Injuries obtained under the influence of drugs might be missed without in-depth social history and appropriate imaging training.
Cyclothymic Disorder: A Cognitive Behavioral Case Formulation
Authors: Bertolucci Ilaria
Published: July 2024

Cyclothymic disorder is recognized as a mild, less severe and subthreshold form of bipolar disorder. The complexity of the disorder leads to difficulties in diagnosis and treatment. A dimensional approach to diagnosis may help identify the goals, and the planning of the psychological intervention. In this paper, a case of cyclothymic disorder is presented, focusing on the cognitive-behavioral conceptualization of the case and its treatment planning.