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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

A Mobile Platform for Measuring Air Pollution in Cities using Gas Sensors

Mölder, Mikael January 2018 (has links)
Although air pollution is one of the largest threats to human health, the data available to the public is often sparse and not very accurate nor updated. For example, there exists only about 5-10 air quality measuring points across the city of Stockholm. This means that the available data is good in close proximity of the sensing equipment but can differentiate much only a couple of blocks away. In order for individuals to receive up to date information around a larger city, stationary measurements are not sufficient enough to get a clear picture of how the current state of the air quality stands. Instead, other methods of collecting this data is needed, for instance by making the measurements mobile. GOEASY is a project financed by the European Commission where Galileo, Europe’s new navigational service, is used to enable more location-based service applications. As part of the GOEASY project is the evaluation of the potential of collaborative applications where users are engaged to help individuals affected by breathing-related diseases such as asthma. This thesis presents the choice of architecture and the implementation of a mobile platform serving this purpose. Using sensors mounted on a range of objects real time air quality data is collected and made available. The result is a mobile platform and connected Android application which by utilizing air quality sensors, reports pollution measurements together with positional coordinates to a central server. Thanks to the features of the underlying systems used, this provides a platform which is accurate and more resilient to exploits compared to traditional location-based services available today. The result allows individuals with respiratory conditions to receive much more accurate and up to date information in a larger resolution. It also serves the purpose of demonstrating the potential of the supporting technology as part of the GOEASY project. / Trots att föroreningar i luften är bland de största hoten mot mänsklig hälsa är den information som finns tillgänglig för allmänheten ofta både gles och inte tillräckligt noggrann eller uppdaterad. Till exempel finns det i hela Storstockholm endast mellan 5–10 luftkvalitetstationer som mäter föroreningar. Detta innebär att den data som finns tillgänglig är bra i närheten av mätutrustningen men kan skilja sig mycket enbart ett par kvarter bort. För att öka mängden information som är tillgänglig till allmänheten räcker inte längre enbart de stationära lösningarna som finns idag för att visa hur de rådande halterna av föroreningar står sig. Andra metoder måste införas, exempelvis genom att nyttja mobila mätningar från en plattform som kan röra sig fritt. GOEASY är ett projekt finansierat av den Europeiska Kommissionen, där Galileo, Europas nya navigationssystem används för att tillåta fler platsbaserade tjänster att äntra marknaden. Som en del av GOEASY projektet ingår evalueringen av potentialen i en applikation där användare samlar in data för att hjälpa individer med andningssvårigheter som astma. Denna avhandling presenterar valen till arkitekturen samt implementationen av en mobil plattform som en del av GOEASY. Lösningen använder sig av mobila luftkvalitetsensorer som kan monteras på en rad olika objekt som samlar data i realtid som görs tillgänglig för allmänheten. Resultatet är en mobil plattform och tillhörande Android applikation som med hjälp av luftkvalitetsensorer rapporterar halten av olika skadliga föroreningar tillsammans med platsinformation till en central server. Tack vare egenskaperna av de underliggande systemen som används, skapas en plattform som är mycket mer precis när det gäller positionering jämfört med liknande system som finns tillgängligt. Det resulterande systemet gör det möjligt för individer med andningssvårigheter att få tillgång till noggrannare samt mer uppdaterad information i större utsträckning än vad som för närvarande är tillgängligt. Systemet fyller även syftet med att demonstrera potentialen i den bakomliggande teknologin som en del av GOEASY.
372

Precision measurement of the e+e− → π + π−(γ ) cross-section with ISR method

Wang, L.-L. 26 May 2009 (has links) (PDF)
Vacuum polarization integral involves the vector spectral functions which can be experimentally determined. As the dominant uncertainty source to the integral, the precision measurement of the %born cross section of $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ as a function of energy from $2\pi$ threshold to 3GeV is performed by taking the ratio of $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ cross section to $e^+e^-\rightarrow\mu^+\mu^-(\gamma)$ cross section which are both measured with {\babar\ }data using ISR method in one analysis. Besides that taking the ratio of the cross sections of the two processes can cancel several systematic uncertainties, the acceptance differences between data and MC are measured using the same data, and the corresponding corrections are applied on the efficiencies predicted by MC which can control the uncertainties. The achieved final uncertainty of the born cross section of $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ in $\rho$ mass region ($0.6\sim0.9$GeV) is 0.54\%. As a consequence of the new vacuum polarization calculation using the new precision result of the $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ cross section, the impact on the SM prediction of muon anomalous magnetic moment $g-2$ is presented, which is also compared with other data based predictions and direct measurement.
373

Theoretical Investigations of pi-pi Interactions and Their Role in Molecular Recognition

Sinnokrot, Mutasem Omar 07 July 2004 (has links)
Noncovalent interactions are of pivotal importance in many areas of chemistry, biology, and materials science, and the intermolecular interactions involving aromatic rings in particular, are fundamental to molecular organization and recognition processes. The work detailed in this thesis involves the application of state-of-the-art ab initio electronic structure theory methods to elucidate the nature of pi-pi interactions. The binding energies, and geometrical and orientational preferences of the simplest prototype of aromatic pi-pi interactions, the benzene dimer, are explored. We obtain the first converged values of the binding energies using highly accurate methods and large basis sets. Results from this study predict the T-shaped and parallel-displaced configurations of benzene dimer to be nearly isoenergetic. The role of substituents in tuning pi-pi interaction is investigated. By studying dimers of benzene with various monosubstituted benzenes (in the sandwich and two T-shaped configurations), we surprisingly find that all of the substituted sandwich dimers considered bind more strongly than benzene dimer. We also find that these interactions can be tuned by a modest degree of substitution. Energy decomposition analysis using symmetry-adapted perturbation theory (SAPT) reveals that models based solely on electrostatic effects will have difficulty in reliably predicting substituent effects in pi-pi interactions.
374

Ανάλυση συστήματος ηλεκτρικής ενέργειας με ηλεκτρονικά ελεγχόμενη συστοιχία πυκνωτών (στατικό αντισταθμιστή)

Καλαμπαλίκης, Ευάγγελος 30 April 2014 (has links)
Η παρούσα διπλωματική ασχολείταιμε τις σύγχρονες μεθόδους που εφαρμόζονται στα συστήματα ηλεκτρικής ενέργειας για την βελτίωση των χαρακτηριστικών τους χρησιμοποιώντας αφενός τις τεχνολογικές εξελίξεις στον τομέα των ημιαγωγικών διακοπτικών στοιχείων και αφετέρου την εγκατεστημένη θεωρία ελέγχου. Στο κεφάλαιο 1 επιχειρείται μια εισαγωγή στις έννοιες των συστημάτων μεταφοράς ηλεκτρικής ενέργειας (ΣΗΕ) καθώς και στην αρχή λειτουργίας τους.Στη συνέχεια γίνεται αναφορά στην έννοια της ποιότητας ισχύος και στα προβλήματα που παρουσιάζονται στα ηλεκτρικά δίκτυα. Τέλος αναφέρονται τα προβλήματα εκείνα που με την πάροδο του χρόνου έκαναν επιτακτική την εισχώρηση της τεχνολογίας των ηλεκτρονικών ισχύος στο πεδίο τους και ιδιαίτερα στην κατεύθυνση της αντιστάθμισης αέργου ισχύοςπου αποτελεί ένα απο τα κυριότερα προβλήματα. Στο κεφάλαιο 2 συνεχίζουμε αναλύοντας τη μορφή που παίρνουν τα σύγχρονα ΣΗΕ μετά την είσοδο της τεχνολογίας των FACTS ξεκινώντας από τα θυρίστορ ,ηλεκτρονικούς διακόπτες ισχύος,που αποτελούν δομικά στοιχεία των νέων διατάξεων και επόμενα τις γενικότερες διατάξεις που χρησιμοποιούνται στα ΣΗΕ που συνδυάζουν τα νέα στοιχεία ακόμα και με τους μηχανικούς διακόπτες που ήταν ο προηγούμενος τρόπος ελέγχου των ΣΗΕ. Στο κεφάλαιο 3 γίνεται μια πιο ενδελεχή αναφορά στα κυκλώματα τεχνολογίας ηλεκτρονικών ισχύος που χρησιμοποιύνται ώστε να πάρουν μορφή οι προηγούμενες διατάξεις ,ξεκινώντας από τη βασική μονάδα του μετατροπέα ημιγέφυρας δομικό στοιχείο των DC/AC μετατροπέων.Ακόμα στο κεφάλαιο αυτό αναφερόμαστε στον έλεγχοτων διατάξεων ,αναλύοντας τα συστήματα αναφοράς και τις τεχνικές που υπάρχουν για να καταστεί δυνατή η οδήγησή τους. Στο κεφάλαιο 4 τα πράγματα γίνονται πιο συγκεκριμένα και αναφερόμαστε στο στατικό αντισταθμιστή (STATCOM).Παρουσιάζονται τα κυκλώματα ελέγχου που περιέχει έτσι ώστε να γίνεται δυνατός ο έλεγχος τάσης είτε διάφορες άλλες δυνατότητες που μπορεί να προσφέρει στο πλαίσιο της καλύτερης λειτουργίας των σύγχρονων ΣΗΕ.Επίσης αναπτύσσεται το μαθηματικό και δυναμικό μοντέλο με τις εξισώσεις στα βήματα του οποίου θα κινηθεί και η προσομοίωση του επόμενου κεφαλαίου. Στο κεφάλαιο 5 γίνεται προσομοίωση της λειτουργίας του στατικού αντισταθμιστή και παρουσιάζονται διάφορα διαγράμματα από τα επιμέρους κυκλώματα που αναδεικνύουν τη λειτουργία του.Κύριο αντικείμενο και εδώ αποτελεί η θεωρία ελέγχου και ιδιαίτερη μνεία γίνεται στην χρησιμοποίηση των PI ελεγκτών εκείνω οι οποίοι ρυθμίζουν παραμέτρους του συστήματος και μετουσιώνουν τη μετάβαση από τα παλαιότερα συστήματα που χρησιμοποιούνταν στα ΣΗΕ όπως ο έλεγχος με μηχανικούς διακόπτες. Στο κεφάλαιο 6 τέλος προχωράμε σε κάποιες ιδέες και προτάσεις για μελλοντική έρευνα ως αποτέλεσμα της ενασχόλησης με την συγκεκριμένη διπλωματική εργασία. / In capter 1 there is an intoduction to the Electrical Power Systems terminology,as well as their function and principles.Next,the meaining of power quality is presented along with the problems that occur at the electrical main grids.More emphsis is given to the ones that gradually enforced the use power electronics for reactive power compensation. In chapter 2,an analysis is made about the form of the modern Electrical Power Systems after the development of the FACT technology,starting from thyristors ,electronic power switches,which are elementsof the new layout and continuing with other modern devices which combine these new elements even with the old mechanical switches. In chapter 3,the electronic power systems' circuits are examined more thorouglyin order to understand the layout of the aforementioned structures,starting from the elementary unit of the half bridge power converter.Moreover,the control of these structures is examined,analyzing the reference systems and the various techniques in order to drive them. Chapter 4, presents the static compensator (STATCOM) along with its control circuits.In addition, the mathematical and dynamic model is developed, forming equations where the simulation of the next chapter is based. In chapter 5,there is a simulation of STATCOM's function (in MATLAB software) and various diagrams are presented showing different variables during its operation.Main purpose of this section is the presentation of the control theory,highlighting the use of PI controllers which adjust the system's parameteres and realize the transition from the older structures used in Electrical Power Systems ,such us mechanical switching. In chapter 6,we present some ideas in terms of future survey as a result of our dealing with the certain thesis
375

Έλεγχος μηχανής συνεχούς ρεύματος τροφοδοτούμενης από τριφασικό πλήρως ελεγχόμενο αντιστροφέα

Μιχαλόπουλος, Ιωάννης 07 July 2015 (has links)
Σήμερα η ανάγκη για δημιουργία ποιοτικών και φθίνων και ανταγωνιστικών βιομηχανικών προϊόντων έχει σαν αποτέλεσμα να χρειαζόμαστε αυτοματισμούς και αυτόματο έλεγχο ηλεκτρικών μηχανών με μεγάλη ακρίβεια και αδιάλειπτη λειτουργία απο διαταραχές του περιβάλλοντος . Επιπλέον το ενεργειακό πρόβλημα που είναι από τα σπουδαιότερα προβλήματα του πλανήτη και του ανθρώπου σήμερα οδηγούν στην ανάγκη ελαχιστοποίησης των ενεργειακών απωλειών με αποτέλεσμα συνήθως να επιθυμούμε λειτουργία των ηλεκτρομηχανικών συστημάτων με μηδενική κατανάλωση/ παραγωγή άεργου ισχύος . Η Ηλεκτρική μηχανή συνεχούς ρεύματος με διέγερση σε σειρά χρησιμοποιείται λόγω των ιδιαίτερων χαρακτηριστικών της σε πολλές εφαρμογές που χρειάζονται υψηλή ροπή εκκίνησης όπως ανυψωτικά μηχανήματα, σιδηροδρομικά οχήματα. Οι ανορθωτές με ελεγχόμενη έναυση αλλά και σβέση κατά PWM προτιμούνται έναντι των διόδων και των θυρίστορς γιατί μας δίνουν περισσότερες δυνατότητες ελέγχου . Η Μοντελοποίηση , σχεδιασμός συστήματος ελέγχου, ευστάθειας του συστήματος για την μηχανή συνεχούς ρεύματος οδηγούμενης από τριφασικό ανορθωτή ερευνάται. Γίνεται εξαγωγή του μοντέλου, στο τριφασικό σύστημα και στο πλαίσιο park, με βάση την δυναμική ανάλυση Εuler -Lagrange . Για την εξαγωγή του μοντέλου γίνεται ακόμα χρήση του Averaging Analysis . Ανάλυση που βασίζεται στην παθητικότητα μάς δείχνει ότι το σύστημα είναι ευσταθές πεπερασμένης εισόδου-πεπερασμένης κατάστασης. Οι ελεγκτές που αναπτύσσονται σε αυτή τη εργασία είναι ο ασαφής ελεγκτής, ο νευροασαφής που χρησιμοποιούνται ευρέως σε μη γραμμικά συστήματα στην βιομηχανία, ο PI σειριακός (cascade) ελεγκτής που συνηθίζεται στις ηλεκτρικές μηχανές. Τέλος επιχειρείται ο σχεδιασμός ενός PI ελεγκτή με υπολογισμό κερδών από νευροασαφή εκτιμητή. Ο ασαφής ελεγκτής σχεδιάζεται με πρόβλεψη σφάλματος και επιτυγχάνει πολύ καλή ρύθμιση των στροφών και καλό έλεγχο στης αέργου ισχύος, εξομοιώσεις επιβεβαιώνουν την απόδοση του ελεγκτή. Ομοίως ισχύουν για τον νευροασαφή ελεγκτή με το πλεονέκτημα μικρότερου υπολογιστικού χρόνου αλλά μειονεκτεί μεγαλύτερης εμφάνισης ενός μόνιμου σφάλματος. Ο PI σειριακός (cascade) επιτυγχάνει άριστη ρύθμιση αέργου ισχύος και καλή ρύθμιση στροφών ενώ ο PI casacde- Anfis μας δίνει ελαφριά καλύτερα αποτελέσματα αλλά αφήνει αρκετές δυνατότητες για περαιτέρω σχεδιασμό και έρευνα. Επίσης γίνεται κάποια ανάλυση για εξαγωγή συμπερασμάτων ευστάθειας και σύγκλισης για τα σύστημα κλειστού βρόχου. Τα αποτελέσματα τα επιβεβαιώνουμε και τα συγκρίνουμε μέσω εξομοιώσεων. / Nowadays , the demand for precise control in industrial applications require the design and development of advanced controllers. Also the energy problem which is one of the most important global problems lead to the need of high energy efficient systems. In industrial applications in most cases ,due to the energy problem , we desire operation with unity power factor. The dc series connected motor is preferred in many application such as railway and levitating systems due to its high starting torque. We choose the 3 -phase pulse width modulation rectifier because of its many capabilities comparison with thyristor rectifiers. Modeling, control design and stability analysis of series connected dc motor fed by three-phase PWM ac/dc voltage converter are investigated. The designed controllers are fuzzy , neuro fuzzy, PI cascade and Anfis- pi cascade controller. The model is obtained via Euler -Lagrange dynamic analysis. Also we used the averaging analysis in order to determine the dynamic model of the system in a-b-c frame and d-q park's frame. We prove the ISS stability of the open loop system based on passivity analysis. The fuzzy use a predictive logic based on the acceleration of the motor, we result excellent precise control of angular velocity and a satisfied control of reactive power. Neuro Fuzzy controller has the same effectiveness with less computational effort but has a possibility to occur a small permanent error in angular velocity. PI cascade controller has as a result a excellent response at reactive power and good response in angular velocity with more less computational effort. ANFIS -PI cascade controller have a bit better results from PI-cascade controllers but it leaves hopes for more optimum designs in feature. Furthermore there are some stability and convergence analysis for the closed loop system. Simulation results verify the effectiveness of each controller for comparison.
376

Control of electromechanical systems, application on electric power steering systems / Contrôle commande des systèmes électromécaniques, application aux systèmes de directions assistées électriques

Yamamoto, Kazusa 08 November 2017 (has links)
De nos jours, la plupart des véhicules sont équipés de Directions Assistées Electriques (DAE). Ce type de systèmes d'aide à la conduite permet de réduire les efforts que le conducteur doit fournir pour tourner les roues. Ainsi, grâce à un moteur électrique, la DAE applique un couple additionnel en accord avec le comportement du conducteur et la dynamique du véhicule. Il est donc nécessaire de développer une commande en couple basée en particulier sur le signal provenant d'un capteur mesurant le couple agissant au niveau de la barre de torsion (correspondant à une image du couple conducteur). Ce composant est donc essentiel au fonctionnement de la DAE. Or, une défaillance de ce capteur entraine le plus souvent une coupure de l'assistance, pouvant mener à un risque d'accidents. Au regard de la sécurité fonctionnelle, un développement d'un mode de sécurité est recommandé, par de plus en plus de constructeurs automobiles. D'autre part, le marché des équipementiers automobiles reste un secteur très concurrentiel où une baisse des coûts de production est un challenge constamment recherché afin de gagner de nouvelles parts de marchés. Cet aspect de réduction du nombre de capteurs et d'analyse de la dynamique du véhicule s'inscrit donc dans le prolongement de la stratégie de sécurité. Cette thèse, menée au sein de JTEKT Europe, aborde ces divers enjeux. Après une présentation des différents systèmes de directions assistés électriques, des modèles sont présentés pour être utilisés lors de la conception de lois de commande et d'estimateurs. Ensuite deux méthodes d'estimation du couple conducteur sujet aux perturbations de la route et aux bruits de mesures sont proposées : la première est un observateur proportionnel intégral (PI) à synthèse mixte $H_infty/H_2$, et la seconde une approche par filtrage $H_infty$. Puis plusieurs stratégies de commande sont proposées suivant deux cas de figures distincts, soit en utilisant un observateur PI qui estime les états du système et le couple conducteur (LQR, commande LPV par retour d'état), soit en faisant abstraction d'estimateur de couple conducteur (commande $H_infty$ par retour de sortie dynamique). Ce dernier aspect présente l'avantage de nécessiter moins de mesures que le précédent. Ces approches ont été validées en simulation et mises en œuvre sur un véhicule prototype où des résultats prometteurs ont été obtenus. / Nowadays, modern vehicles are equipped with more and more driving assistance systems, among them Electric Power Steering (EPS) helps the driver to turn the wheels. Indeed, EPS provides through an electric motor, an additional torque according to the driver's behaviour and the vehicle's dynamics to reduce the amount of effort required to the driver. Therefore, a torque control is developed based on the torque sensor signal which measures in practice the torsion bar torque (corresponding to an image of the driver torque). Consequently, this component is essential to the functioning of EPS systems.Indeed, a torque sensor failure usually leads to shut-off the assistance which may increase the risk of accident. Regarding functional safety, a back-up mode is recommended and required by more and more car manufacturers. On the other hand, a major challenge for automotive suppliers is to reduce cost production in order to meet growing markets demands and manage in the competitive sector. This issue considering a reduction of sensors' numbers and analysis of vehicle's dynamics is therefore an extension of applying the safety strategy. This thesis, carried out within JTEKT Europe, addresses these various issues.After introducing an overview of the different EPS systems, some models used for the design of controllers and estimators are presented. Then, two methods to estimate the driver torque subject to road disturbances and noise measurements are proposed: the first is a proportional integral observer (PI) with mixed synthesis $H_infty / H_2 $, whereas the second is an $ H_infty $ filtering approach. Then, several control strategies are proposed according to two different cases, either by using a PI observer which estimates the system states and the driver torque (LQR, LPV feedback control) or by not taking into account the driver torque estimation ($ H_infty $dynamic output feedback control). This latter approach has the advantage to require less measurements than the previous one. These approaches have been validated in simulation and implemented on a prototype vehicle where promising results have been obtained.
377

Confinement d’oligomères π-conjugués dans des nanotubes de carbone mono-feuillets : intéractions, dynamique et structure / Confinement of π-conjugated oligomers inside single-walled carbon nanotubes : interaction, dynamics and structure

Lopes Selvati, Ana Carolina 16 December 2016 (has links)
Ce travail est dédié à l’étude de l’encapsulation de molécules organiques photoactives dans des nanotubes de carbone mono-feuillets. L’effet de confinement sur les propriétés vibrationnelles , structurales, et les interactions entre les sous-systèmes est étudié en fonction de la taille des nanotubes. La première partie du manuscrit est consacrée à l’étude du confinement de diméthylquaterthiophènes dans les tubes. La dynamique vibrationnelle des molécules confinées est étudiée par diffusion inélastique des neutrons et par des simulations DFT. L’étude des interactions entre les deux sous-systèmes, en termes de transfert d’énergie et de transfert de charge, est réalisée en combinant des études de photoluminescence et de Raman. La nature des transferts de charge dépend de la taille du nanotube. Pour des tubes de petits diamètres (<1.1nm), un transfert de charge photo-induit est obtenu lorsque la longueur d’excitation correspond à l’absorption de la molécule. La deuxième partie est dédiée à l’étude de l’organisation structurale de molécules de phtalocyanine encapsulées à l’intérieur des nanotubes. Ce travail combine des études expérimentales par diffraction neutronique et spectroscopie Raman à pression ambiante et sous hautes pressions. Les études structurales sont confrontées à des simulations par dynamique moléculaire. / This work is dedicated to the study of the encapsulation of photoactive molecules within single wall carbon nanotubes. The confinement effect on vibrational, structural and interactions between host and guest is studied as a function of nanotube size. The first part of the manuscript is dedicated to the confinement of dimethyl quaterthiophene within carbon nanotubes. Vibrational dynamics for the encapsulated molecules is studied coupling neutron scattering and DFT simulations. Interactions molecule/nanotube, in terms of energy transfer and charge transfer are studied combining photoluminescence and Raman spectroscopies. The nature of charge transfers depends on the size of the nanotube. For small diameters (>1,1nm) a photoinduced charge transfer is obtained when the excitation wavelength matches the absorption of the molecule. The second part of the manuscript focuses on the structural organization of encapsulated phthalocyanine molecules. This work combines neutron diffraction and Raman spectroscopy experimental studies at room and high pressures. Structural studies are discussed together with molecular dynamics simulations.
378

Personality and academic achievement in nniversity students / Personalidad y rendimiento académico en estudiantes universitarios

Niño de Guzmán, Isabel, Calderón, Arturo, Cassaretto, Mónica 25 September 2017 (has links)
The correlations among personality, academic performance and other variables in 170 university students were studied, using two instruments validated into the population: the NEOPJ-R, and the EPPS. Other variables as age, study level, self perception of academic achievement and self perception of motivation, and sources of support were included. Jt was confirmed the reliability and validity of both tests and the correlations between them. The results showed associations among academic performance and conscientiousness, endurance,change, and aggression. The academic performance was better explained by achievements triving, deliberation, change, self perception of academic achievement and age. / Se investigó la relación entre personalidad, rendimiento académico y otras variables en 170 universitarios, mediante dos instrumentos validados para esta población: el NEO PI-R de Costay McCrae y el EPPS de Edwards4• Se consideró las variables edad, ciclo académico, percepcióndel rendimiento, de la propia motivación para estudiar, y fuentes de apoyo. Se confirmo la validez y confiabilidad de ambas pruebas y sus respectivas correlaciones. Se encontraron asociaciones entre el rendimiento y conciencia, perseverancia, cambio y agresión. El rendimiento fue mejor explicado por la aspiraciones de logro, reflexión, cambio, percepción del rendimientoy edad del estudiante.
379

Gestão dos recursos hídricos em Jaicós-PI

Maria dos Ramos de Brito 02 July 2015 (has links)
Os recursos hídricos constituem um dos elementos mais acentuados na discussão das questões ambientais colocando-se como um dos principais desafios a serem encarados pela humanidade no século XXI. Esta pesquisa verifica o atual momento de seca vivido no Nordeste remetendo a uma conscientização do uso devido dos recursos hídricos propondo a existência de uma gestão dos recursos hídricos ser de fundamental importância na preservação dos mesmos. Apresenta como objetivo geral analisar a gestão dos recursos hídricos no município de Jaicós no Estado do Piauí visando avaliar os procedimentos que estão sendo tomados para a conservação, distribuição e organização destes recursos disponíveis, fornecidos pelo poder público através de preceitos éticos. Expõem sobre a gestão dos recursos hídricos no município de Jaicós no Estado do Piauí discorrendo sobre os efeitos que a má gestão dos poderes públicos acomete no município quanto à questão da gestão. Justifica-se a necessidade de estudos que avaliem a disponibilidade e a demanda hídrica dentro de uma perspectiva de sustentabilidade na utilização deste recurso, valendo-se do estímulo decorrente da criação de um novo arcabouço legal que dá suporte à gestão dos recursos hídricos pautados nos preceitos éticos. Menciona ao concluir a pesquisa que o que mais falta às nossas cidades, inclusive Jaicós, não é água, mas sim determinado padrão cultural que ajunte ética e melhore a eficiência do desempenho político dos governos, da sociedade organizada e das ações públicas e privadas, responsáveis que são por agenciar o desenvolvimento econômico em geral e a proteção da água doce, em particular. / Water resources constitute one of the most accentuated elements in the discussion of environmental issues being placed as one of the main challenges to be faced by humanity in the 21st century. This research looks at the current moment of drought that is being experienced in the Northeast remitting to an awareness raising about the proper use of water resources and to a proposal that the existence of a management of the water resources is of fundamental importance to the preservation of these. It presents as a general goal the analysis of the management of water resources in the municipality of Jaicós in the state of Piauí aiming to evaluate the procedures which are being implemented for the conservation, distribution and organization of the available resources, furnished by the public power through ethical precepts. It presents the management of the water resources in the municipality of Jaicós in the state of Piauí discoursing about the effects which a bad management of the public powers have on the municipality related to the issue of management. The need for studies which evaluate the water availability and demands within a perspective of sustainability in the use of this resource is justified making use of the stimulus resulting from the creation of a new legal framework which supports the management of water resources based on ethical principles. The research mentions at the end that what is lacking in most of our cities, including in Jaicós, is not water but a certain cultural pattern which adds in ethics and improves the efficiency of the political work of the governments, of organized society and of public and private actions, since they are responsible for managing the economic development in general and the protection of potable water in particular.
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Ilha de calor e a influência no conforto térmico da região integrada de desenvolvimento da grande Teresina (ride). / Heat island and the influence in the thermal comfort of the intefrated region of development of the grande Teresina (ride)

Santiago, Dimas de Barros 19 April 2017 (has links)
The urban heat islands are effects where the temperature of the urban areas is greater than the surrounding areas and rural areas, as a result of the modification and/or substitution of the vegetation by areas ithout vegetation or asphaltic areas, modifying the ambient climate and the local human thermal comfort , The aim of the study was to observe the phenomenon of the Islands of Urban Heat (ICU) in Teresina-PI and Timon-MA and the relation with thermal comfort of the study area, through thermal remote sensing and the human thermal comfort index , Effective Temperature. Six satellite images were used, four obtained by Landsat-5 TM satellite, acquired in the Catalog of Images - DGI - INPE and two obtained from Landsat-8 on the USGS website. The images correspond to the passage of the satellite at points 219, orbits 63 and point 219, orbit 64 dates, Landsat 5: 20 June 2004, 10 June 2006, 01 July 2008, 01 July 2008. Landsat 8: July 18, 2014 and July 23, 2016. Hourly, daily and monthly data of relative air humidity and average air temperature, for the years of study, provided by the National Institute of Meteorology (INMET), for the calculation of the Human Thermal Comfort Index. For the image processing, models were developed using the Model Maker tool of the ERDAS Imagine 9.2 program and Qgis 2.12.1, having images necessary to obtain the temperature on the terrestrial surface, which will serve as the basis for the identification of the heat islands and the Effective temperature index, to observe the comfort of the cities under study. In the study, we observed the temperature difference between the Teresina-PI and Timon-MA cities and areas without urbanization (more vegetated, without soil modification), where there was a variation between approximately 6 ° C and 9 ° C, When compared surrounding areas and the city. The relationship between heat islands and human thermal comfort was thus concluded, as cities develop and occur at surface modification, temperatures increase, consequently human discomfort increases, since the human being is influenced by the In which he lives. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / As ilhas de calor urbanas são efeitos onde a temperatura das áreas urbanas são maiores que as áreas próximas e áreas rurais, consequência da modificação e/ou substituição da vegetação por áreas sem vegetação ou áreas asfálticas, modificando o clima ambiente e o conforto térmico humano local, assim o objetivo do trabalho visou observar o fenômeno Ilhas de Calor Urbanas (ICU), em Teresina-PI e Timon-MA e a relação com conforto térmico da área de estudo, por meio do sensoriamento remoto termal e do Índice de conforto térmico humano, Temperatura Efetiva. Foram utilizadas seis imagens de satélites, quatro obtidas pelo satélite Landsat-5 TM, adquiridas no Catálogo de Imagens - DGI - INPE e duas obtidas do Landsat-8 no site da USGS. As imagens correspondem à passagem do satélite nos pontos 219, órbitas 63 e ponto 219, órbita 64 datas, Landsat 5: 20 de Junho de 2004, 10 de Junho de 2006, 01 de Julho de 2008, 01 de Julho de 2008. Landsat 8: 18 de Julho de 2014 e 23 de Julho de 2016. Dados horários, diários e mensais de umidade relativa do ar e temperatura média do ar, para os anos de estudo, cedidos pelo Instituto Nacional de Meteorologia (INMET), para o cálculo do Índice de Conforto Térmico Humano. Para o processamento das imagens foram desenvolvidos modelos através da ferramenta Model Maker do programa ERDAS Imagine 9.2 e o Qgis 2.12.1, tendo imagens necessárias para a obtenção da temperatura na superfície terrestre, que servirá como base para a identificação das ilhas de calor e o índice de temperatura efetiva, para observar o conforto das cidades em estudo. No estudo observou-se a diferença de temperatura entre a área das cidades de Teresina-PI e Timon-MA e as áreas sem urbanização (mais vegetada, sem modificação do solo), onde houve uma variação entre aproximadamente 6°C a 9°C, quando comparado áreas circunvizinhas e a cidade. Concluiu-se assim a relação entre as ilhas de calor e o conforto térmico humano, assim à medida que as cidades se desenvolvem e ocorre à modificação da superfície, as temperaturas aumentam, consequentemente aumenta o desconforto humano, visto que o ser humano sofre influência do meio em que vive.

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