24 research outputs found
Environmental contestation in China: Motives and impact
No full textEnvironmental legislation in China prescribes Public Participation in Environmental Impact Assessment to be arranged by the initiator of a project. Nevertheless concerns of effected citizens are often neglected and not addressed in the impact studies. The rising public environmental awareness and realization of health risks related to the proposed activity can lead to outbreaks of public protests and mass events, which may result in cancellation of such projects. In this paper some recent cases of contestation in China are presented and their impact on environmental decision-making analysed. It shows that the Chinese public does have an impact on policy making and stimulates the government to sharpen environmental regulation and procedures.Policy Analysi
Aerodynamic analysis of wind turbine blade equiped with flaps and slats
No full text95 σ.Στην παρούσα εργασία γίνεται μελέτη πτερυγίου μεταβλητής γεωμετρίας στην ακμή εκφυγής (flap) καθώς και στην ακμή πρόσπτωσης (slat). Έχει στόχο να ελέγξει την επίδραση που έχει η μεταβλητή γεωμετρία στην τελική αποδιδόμενη ισχύ της ανεμογεννήτριας. Για τον σκοπό αυτό διεξήχθη ανάλυση τυπικής διάταξης αεροτομής με γεωμετρικά μεταβαλλόμενη ακμή εκφυγής αλλά και ακμής πρόσπτωσης σε σταθερές γωνίες, αρχικά σε πτερύγιο χωρίς πάχος και έπειτα σε πτερύγιο με πάχος.
Η αεροδυναμική επίλυση του προβλήματος έγινε μέσω του υπολογιστικού πρότυπου General Unsteady Vortex Particle (GENUVP). Ο κώδικας αυτός αποτελεί ένα σύνθετο και ιδιαίτερο ευέλικτο υπολογιστικό εργαλείο με την δυνατότητα επίλυσης μη μόνιμης ασυμπίεστης και μη συνεκτικής ροής γύρω από περίπλοκες γεωμετρίες σωμάτων.The present thesis is a study of a trailing and leading edge blade using variable geometry. Its goal is to control the impact of the variable geometry in the final power of wind turbine. For this reason we conducted analysis of typical airfoil with geometrically varied flap and slat in constant angles, initially in thin and then in thick blade.
The aerodynamic solution of the problem has been made possible using the code General Unsteady Vortex Particle (GENUVP). This code is complex and very flexible tool, which give us the possibility of solving uniform, incompressible and inviscid airflow. Main advantage of GENUVP, especially due to the particle approximation of the wake, is its capability of easily treating complex geometries and solid-wake interaction problems.Δημοσθένης Α. Μιχαλακέα
From rural to urban settings: life on the margins in the short stories of Dimosthenis Voutiras
No full textThis thesis has been focused on the research of the literary characters in the short stories of Dimosthenis Voutiras, one of the pioneer literary writers of his generation. More specifically, the explanatory interest turned to the characters which have been socially marginalised. These characters are depicted in short stories that cover a chronological period from the beginning of the author’s writing presence and ends at the middle of the Interwar Era. This thesis has been developed methodologically by utilising textual and extratextual criteria, making use of hermeneutic tools from narratology as well as from the scientific field of sociology. More precisely, the theoretical compass of the thesis was a narrative approach which is based on the wider theoretical framework of Gerard Genette, but also the typology of Dorrit Cohn about a research regarding the conscience of the fictional characters throughout a more stylistic type of analysis. In addition to this, vital findings regarding the depiction of the characters were emerged from the use of Mikhail Bakhtin's theory about dialogism and his conclusions concerning elements of Carnival. Furthermore, the approach to the behaviour and the identity of the socially marginalised characters, as they are attributed by the author, was achieved through cultural studies, and more particularly through the theoretical studies of Pierre Bourdieu regarding the life models of the popular (lower) class. As far as the categorisation of the characters is concerned, the typology which was used throughout the thesis was mainly that of Shlomith Rimmon – Kenan. The conclusions regarding the attribution of the social imprint and the political and philosophical ideas of the characters, place those characters into the spectrum of verisimilitude. Η παρούσα διατριβή επικεντρώθηκε στη μελέτη των λογοτεχνικών χαρακτήρων στα διηγήματα του Δημοσθένη Βουτυρά. Πιο συγκεκριμένα, το ερμηνευτικό ενδιαφέρον στράφηκε στους χαρακτήρες του κοινωνικού περιθωρίου, όπως αυτοί αποτυπώνονται σε διηγήματα που καλύπτουν χρονικά μια περίοδο από την αρχή της συγγραφικής παρουσίας του λογοτέχνη ως τα μέσα της μεσοπολεμικής περιόδου. Μεθοδολογικά η διατριβή αναπτύχθηκε αξιοποιώντας κειμενικά και εξωκειμενικά κριτήρια, με ερμηνευτικά εργαλεία από την αφηγηματολογία αλλά και το επιστημονικό πεδίο της κοινωνιολογίας. Πιο ειδικά, θεωρητικές πυξίδες αποτέλεσαν, η αφηγηματολογική προσέγγιση βάσει του ευρύτερου θεωρητικού σχήματος του Gerard Genette και η τυπολογία της Dorrit Cohn για τη μελέτη της συνείδησης των μυθοπλαστικών προσώπων σε μια πιο υφολογικού τύπου ανάλυση, ενώ σημαντικά ευρήματα για την αποτύπωση των χαρακτήρων αναδύθηκαν από την αξιοποίηση της θεωρίας του Bakhtin για τη διαλογικότητα και των συμπερασμάτων του σχετικά με το καρναβαλικό στοιχείο. Επιπλέον, η προσέγγιση της συμπεριφοράς και της ταυτότητας των περιθωριακών χαρακτήρων όπως τους αποδίδει ο συγγραφέας έγινε μέσω των πολιτισμικών σπουδών και ειδικότερα των θεωρητικών μελετών του Pierre Bourdieu, αναφορικά με τα μοντέλα ζωής της λαϊκής τάξης. Για την κατηγοριοποίηση των χαρακτήρων χρησιμοποιήθηκε κυρίως το μοντέλο της Shlomith Rimmon – Kenan. Τα συμπεράσματα σχετικά με την απόδοση του κοινωνικού αποτυπώματος, των πολιτικών και φιλοσοφικών ιδεών, τοποθετούν τους χαρακτήρες του Βουτυρά στο φάσμα της ρεαλιστικής αφήγησης.
Ion current sensing for controlled auto ignition in internal combustion engines
No full textEnvirom-nental pollution is a subject that needs urgent addressing. Since the internal combustion engine has its fair share of accountability on this, research on techniques for increasing engine efficiency and emissions is necessary. Controlled Auto Ignition is a promising combustion mode, which increases fuel efficiency while also reducing NOx emissions to negligible levels. This Thesis concentrates on the implementation of this mode through experimental research, on an engine equipped with a fully variable valvetrain. Investigation of the operational window, emissions, fuel consumption, thermodynamic efficiency is carried out and ways to improve on these are discussed. The governing consideration, however, is the control method for this rather intricate combustion mode. As such, experimental data acquisition and analysis of ion current under the whole operating spectrum, from spark ignition to full autoignition is made. It is found that the expected gains in fuel consumption and emissions are realized. In addition, ion current proves to be a very powerful and cost effective tool for engine monitoring, diagnosis and control. The author concludes that Controlled Auto Ignition is a viable proposition for mass production engine designs and that ion current, although not absolutely vital for engine control, considerably increases engine control thus allowing for greater operating window under autoignition, without compromising reliability or cost.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Universal Expressions for the Polarization and the Depolarization Factor in Homogeneous Dielectric and Magnetic Spheres Subjected to an External Field of Any Form
No full textSpherical structures of dielectric and magnetic materials are studied intensively in basic research and employed widely in applications. The polarization, (Figure presented.) (P for dielectric and M for magnetic materials), is the parent physical vector of all relevant entities (e.g., moment, (Figure presented.), and force, F), which determine the signals recorded by an experimental setup or diagnostic equipment and configure the motion in real space. Here, we use classical electromagnetism to study the polarization, (Figure presented.), of spherical structures of linear and isotropic—however, not necessarily homogeneous—materials subjected to an external vector field, (Figure presented.) (Eext for dielectric and Hext for magnetic materials), dc (static), or even ac of low frequency (quasistatic limit). We tackle an integro-differential equation on the polarization, (Figure presented.), able to provide closed-form solutions, determined solely from (Figure presented.), on the basis of spherical harmonics, (Formula presented.). These generic equations can be used to calculate analytically the polarization, (Figure presented.), directly from an external field, (Figure presented.), of any form. The proof of concept is studied in homogeneous dielectric and magnetic spheres. Indeed, the polarization, (Figure presented.), can be obtained by universal expressions, directly applicable for any form of the external field, (Figure presented.). Notably, we obtain the relation between the extrinsic, (Figure presented.), and intrinsic, (Figure presented.), susceptibilities ((Formula presented.) and (Formula presented.) for dielectric and (Formula presented.) and (Formula presented.) for magnetic materials) and clarify the nature of the depolarization factor, (Figure presented.), which depends on the degree l—however, not on the order m of the mode (Formula presented.) of the applied (Figure presented.). Our universal approach can be useful to understand the physics and to facilitate applications of such spherical structures. © 2025 by the author
The image of the Greeks in the greek (codex H) and aragonese (Arag.) Chronicle of Morea
No full textThe study examines the image of the Greeks in two of the codices of the Chronicle of Morea, the H and the Arag ., texts of the 14th century, with the lost prototype tracing back to t he start of the same century. The image of the G reeks (which are usually called Ρωμα?οι and griegos respectively in the two texts )), is directly linked with the identity of the authors a nd the targeting of the texts ? composition The author of H aligns wit h the Franks, he disp arages the Greeks of Constantinople, while exhibiting a more positive attitude about the local Greeks of Morea. He does not hesitate to distort historical reality it self in order to achieve his goals, which are praising the Villehardouins and the nostalgic reminiscing of an era that had been lost for good. On the other hand, on the Aragonese text, the author’ s stance on the Greeks and the Franks is generally negative. He, same as before, is positive regarding the local Greeks of Morea . The author never align s himself with the Francs, which makes him more objective. He is mainly interested in the subjects that relate to the Kingdom of Aragon, while his stance is influenced by the fact that his work is completed not long after the described events, comissioned by an prominent ex administrator of Morea
A Classification of NoSQL Data Stores Based on Key Design Characteristics
No full textAbstractTraditional Relational Database Management Systems are continuously being replaced by NoSQL data stores as a result of the growing demand for big data applications. The emergence of a large number of implementations of such like systems is a contributing indicator. This paper deals with the analysis of some key design characteristics of NoSQL systems and uses these for their characterization based on their capabilities. Furthermore, it highlights the relationship between NoSQL systems and cloud infrastructures and explains the impact that the existence of one has to the other
Does the phosphorylation of MAP65-1 correlate with the effects of Cr(VI) on Arabidopsis thaliana microtubules?
No full textKey message: MAP65-1 phosphorylation mediates Cr(VI)-induced microtubule disruption in plants. Abstract: Chromium (Cr) exists in two prevalent forms in the environment: trivalent Cr(III) and hexavalent Cr(VI). While Cr(III) can benefit plants as a micronutrient, Cr(VI) is highly toxic and disrupts essential physiological, biochemical, and cellular processes in plants. Plant cell microtubules (MTs) are particularly susceptible to Cr(VI) toxicity, with MAP65-1, a key microtubule-associated protein, playing a crucial role in stabilizing MTs by forming cross-bridges between them. The stability function of MAP65-1 is influenced by its phosphorylation status: phosphorylation causes MAP65-1 to detach from MTs during different cell cycle phases. This study investigated how Cr(VI) affects MAP65-1 presence on cortical MTs in Arabidopsis thaliana roots and hypocotyls. Seedlings expressing GFP:AtMAP65-1 and its non-phosphorylatable variant, AtMAP65-19A (GFP:AtMAP65-19A), were exposed to 100 μM potassium dichromate (K2Cr2O7, Cr(VI)) on ½ MS solid medium for 24 or 48 h. Confocal laser scanning microscopy (CLSM) revealed that Cr(VI) began impacting cortical MTs within 24 h. The signal intensity of GFP indicated a significant reduction in MAP65-1 presence, whereas the GFP:AtMAP65-19A signal remained stable and MTs were unaffected. These results suggest that Cr(VI) toxicity to MTs is linked to MAP65-1’s phosphorylation status. © The Author(s) 2025
Which Are the Critical Measures to Assess the Driving Performance of Drivers with Brain Pathologies?
No full textAbstractDriving requires possessing cognitive, motor and visual skills and drivers need to have adequate motor strength, coordination and speed. More importantly, cognitive skills including concentration, attention, adequate visual perceptual skills, insight and memory must be present. The normal ageing process leads to declines in these motor and cognitive skills, and when combined with a brain pathology, it may significantly impair the person's driving performance, especially when unexpected incidents occur. The objective of this paper is to identify the critical driving performance measures in which drivers with cognitive impairments significantly deviate from the general population, through a driving simulator experiment. The brain pathologies considered concern Alzheimer's disease (AD), Parkinson's disease (PD) and Mild Cognitive Impairment (MCI). More analytically, a full neurological and neuropsychological assessment was carried out at the “ATTIKON” General Hospital in Athens, by neurologists and neuropsychologists of the UoA. Then, participants drove at the driving simulator of the NTUA. The driving tasks included driving in urban and rural road environment, while various unexpected incidents were scheduled to occur during the drives. The driving performance of 109 drivers with cognitive impairments (MCI, AD or PD) was compared to the driving performance of 31 healthy drivers of similar demographics. For each driver, the following driving performance measures were calculated and examined: speed, speed variability, lateral position, lateral position variability, headway, headway variability, and reaction time. All these parameters were compared to the range of “typical” values of the respective distribution of healthy drivers, and significant deviations from the “typical” distribution were identified. Results indicated that group of patients had various difficulties in driving performance compared with the control drivers. More specifically, more than 50% of the patients had extremely low mean speeds, and they often had lower speed variability (in 40% of the cases) than controls. Regarding the lateral position, the patients had difficulty in positioning the vehicle in the lane, and more than 1 out of 5 patients had very large variability in their lateral position. Also, 44% of the drivers with a brain pathology kept very large mean headways from the vehicle ahead. Finally, 50% of patients had very slow reaction times in unexpected incidents; in rural area 70% of the patients had reaction times larger than 2seconds
Investigating the Effect of Area Type and Traffic Conditions on Distracted Driving Performance
No full textAbstractAlthough driver distraction can be considered as part of everyday driving it constitutes a basic contributory factor for increased risk for road accidents internationally. Within this content, cell-phone use and conversation with passenger are two critical in-vehicle distraction conditions with respect to driver behavior and safety. The objective of this research is the investigation of the effect of area and traffic conditions on driving performance of drivers while talking on the mobile phone or conversing with the passenger. For this purpose, a large driving simulator experiment is carried out, in which 95 drivers from all different age groups (young, middle aged and older) were asked to drive under different types of distraction (no distraction, conversation with passenger, cell phone use) in rural and urban road environment, in low and high traffic. In the next step, an appropriate modelling methodology has been developed, including first descriptive analysis in order to explore the large database. Then generalized linear models as well as generalized linear mixed models regarding average speed and reaction time were implemented in order to estimate the effect of the examined distraction sources as well as area and traffic characteristics on driving behaviour and road safety. Results indicate that female drivers, especially in rural areas, were found to have the worst reaction times, while being distracted (either conversing with a passenger or talking on the cell phone). This is probably explained by the fact that in urban area, the complex road environment alerts the drivers in order to self-regulate their driving to compensate for any decrease in attention to the driving task. Furthermore, regarding average speed, it is observed that in rural areas drivers reduce the speed while distracted either by talking on the mobile phone (older drivers) or by conversing with the passenger (young and middle aged drivers), especially at high traffic volume while in urban areas suggesting a driver's compensatory behaviour. The next steps of the present research could focus on the investigation of the impact of mobile phone use, not only when the drivers talk on mobile phone using a hand-held device, but also when they use a hands-free device, a Bluetooth, or when they type messages
