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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.
31

Προσδιορισμός εκπομπών αέριων ρύπων στα αστικά κέντρα της Ελλάδας

Δημοπούλου, Μαρία 23 October 2007 (has links)
Στα πλαίσια της εργασίας θα ασχοληθούμε με την μεθοδολογία υπολογισμού των ρυθμών εκπομπής αέριων ρύπων στα αστικά κέντρα της Ελλάδας. Οι πήγες της ατμοσφαιρικής ρύπανσης διακρίνονται σε σημειακές, επιφανειακές, ανθρωπογενείς και φυσικές. Στο πρώτο στάδιο θα γίνει καταγραφή και κατηγοριοποίηση των διαφόρων πηγών για τις Ελληνικές συνθήκες με βάση την διεθνή βιβλιογραφία. Οι μέθοδοι προσδιορισμού των ρυθμών εκπομπής θα διερευνηθούν. Συνήθως οι υπολογισμοί απαιτούν δυο ειδών παραμέτρους: την ένταση μιας δραστηριότητας (π.χ πόσα χιλιόμετρα διανύονται σε μια περιοχή από τα αυτοκίνητα μιας ορισμένης κατηγορίας σε μια περιοχή), και τον ρυθμό εκπομπής ανά μονάδα της δραστηριότητας (π.χ εκπομπές οξειδίων του αζώτου ανά χιλιόμετρο). Ανάλογα με την πηγή οι μέθοδοι μπορεί να είναι πιο πολύπλοκοι ή να απαιτούν την γνώση μεταβλητών που δεν είναι εύκολο να βρεθούν. Οι διαφορετικές προσεγγίσεις θα συγκριθούν τόσο με βάση την ακρίβεια τους όσο και με την δυνατότητα εφαρμογής τους στην Ελλάδα. Το τελικό αποτέλεσμα της εργασίας θα είναι μια αναλυτική μεθοδολογία υπολογισμού των εκπομπών ρύπων σε μια Ελληνική πόλη και συγκεκριμένα στην πόλη της Πάτρας, όπου θα μελετηθεί η εκπομπή αέριων ρύπων από τα επιβατικά πλοία τα οποία χρησιμοποιούν το λιμάνι της Πάτρας. Η παρούσα εργασία θα στοχεύσει στον προσδιορισμό της συγκέντρωσης αέριων ρύπων (σωματιδίων PM) στο αστικό κέντρο της Πάτρας, λαμβάνοντας ως πηγή ρύπων τα επιβατικά πλοία που παραμένουν στο Λιμάνι της Πάτρας. Η συγκέντρωση των αέριων ρύπων τέλος, θα υπολογισθεί με χρήση της Gaussian Plume Formula [JS Seinfeld and SN Pandis: “Atmospheric Chemistry and Physics: From Air Pollution to Climate Change”, 2nd edition, John Willey & Sons, INC]. / -
32

Concentração de bauxita por flotação reversa. / Concentration of bauxite via reverse froth flotation.

Renata Kurusu Gancev 16 June 2009 (has links)
O presente trabalho propõe a concentração da bauxita presente em um rejeito fino gerado na usina de beneficiamento da Companhia Brasileira de Alumínio (CBA), agora denominada Votorantim Metais Alumínio, em Itamarati de Minas (MG), através da flotação reversa da sílica, sob a forma de quartzo. Como os minerais de ferro e titânio acompanham a bauxita, é necessário fazer separação magnética para eliminá-los do concentrado final. O concentrado de ferro e titânio pode ser utilizado como aditivo para fabricação de cimento portland. O rejeito de sílica pode ser utilizado como areia para construção civil ou na própria mina em manutenção de vias de acesso. Os experimentos sistemáticos em bancada foram realizados em célula de flotação mecânica, primeiramente, com minério de uma amostragem realizada em 2004. Determinadas as dosagens ótimas dos reagentes (coletor e depressor), partiu-se para a flotação com etapas cleaner e scavenger para definir o balanço de massas e verificar o comportamento do processo. Para validar as conclusões do trabalho experimental, foi feita nova amostragem na usina de beneficiamento de Itamarati de Minas, em julho de 2005, e, com este minério, o experimento de flotação com recirculação de produtos em um circuito em bancada composto por cinco etapas rougher, cleaner e scavenger. Partindo-se de uma alimentação nova com 11,6% de alumina aproveitável, chegou-se a um concentrado com teor de 52,6% no final do circuito, após a separação magnética, com recuperação em massa de 13,3% e recuperação de alumina aproveitável de 60,4%. / The present work proposes bauxite concentration using quartz flotation from a product so far considered a tailing, from the ore processing plant of Companhia Brasileira de Alumínio (CBA), now called Votorantim Metais Alumínio, at Itamarati de Minas (MG). A magnetic separation operation is also necessary to eliminate iron and titanium contaminants. Both products from this beneficiation process can have an industrial destination: iron and titanium concentrate can be used as a portland cement charge and the quartz can be used as construction sand in mine or in road maintenance. Systematic experiments were performed on bench cell froth flotation using the remaining ore sample taken in a 2004 campaign. The optimum collector and depressant dosages were found, followed by a flotation test with cleaner and scavenger that determined the mass balance and confirmed the process behavior. To validate these conclusions a fresh ore sample was taken in July 2005. A new simulation of the flotation circuit by locked cycle with five steps rougher, cleaner and scavenger in bench scale was done with this sample. From an 11,6% alumina feed, a 52% Al2O3 alumina concentrate was achieved, after magnetic separation. The mass recovery was 13,3% and the available alumina recovery was 60,4%
33

A neurophysiological examination of voluntary isometric contractions : modulations in sensorimotor oscillatory dynamics with contraction force and physical fatigue, and peripheral contributions to maximal force production

Fry, Adam January 2016 (has links)
Human motor control is a complex process involving both central and peripheral components of the nervous system. Type Ia afferent input contributes to both motor unit recruitment and firing frequency, however, whether maximal force production is dependent on this input is unclear. Therefore, chapter 2 examined maximal and explosive force production of the knee extensors following prolonged infrapatellar tendon vibration; designed to attenuate the efficacy of the homonymous Ia afferent-α-motoneuron pathway. Despite a marked decrease in H-reflex amplitude, indicating an attenuated efficacy of the Ia afferent-α-motoneuron pathway, both maximal and explosive force production were unaffected after vibration. This suggested that maximal and explosive isometric quadriceps force production was not dependent upon Ia afferent input to the homonymous motor unit pool. Voluntary movements are linked with various modulations in ongoing neural oscillations within the supraspinal sensorimotor system. Despite considerable interest in the oscillatory responses to movements per se, the influence of the motor parameters that define these movements is poorly understood. Subsequently, chapters 3 and 4 investigated how the motor parameters of voluntary contractions modulated the oscillatory amplitude. Chapter 3 recorded electroencephalography from the leg area of the primary sensorimotor cortex in order to investigate the oscillatory responses to isometric unilateral contractions of the knee-extensors at four torque levels (15, 30, 45 and 60% max.). An increase in movement-related gamma (30-50 Hz) activity was observed with increments in knee-extension torque, whereas oscillatory power within the delta (0.5-3 Hz), theta (3-7 Hz), alpha (7-13 Hz) and beta (13-30 Hz) bands were unaffected. Chapter 4 examined the link between the motor parameters of voluntary contraction and modulations in beta (15-30 Hz) oscillations; specifically, movement-related beta decrease (MRBD) and post-movement beta rebound (PMBR). Magnetoencephalography (MEG) was recorded during isometric ramp and constant-force wrist-flexor contractions at distinct rates of force development (10.4, 28.9 and 86.7% max./s) and force output (5, 15, 35 and 60%max.), respectively. MRBD was unaffected by RFD or force output, whereas systematic modulation of PMBR by both contraction force and RFD was identified for the first time. Specifically, increments in isometric contraction force increased PMBR amplitude, and increments in RFD increased PMBR amplitude but decreased PMBR duration. Physical fatigue arises not only from peripheral processes within the active skeletal muscles but also from supraspinal mechanisms within the brain. However, exactly how cortical activity is modulated during fatigue has received a paucity of attention. Chapter 5 investigated whether oscillatory activity within the primary sensorimotor cortex was modulated when contractions were performed in a state of physical fatigue. MEG was recorded during submaximal isometric contractions of the wrist-flexors performed both before and after a fatiguing series of isometric wrist-flexions or a time matched control intervention. Physical fatigue offset the attenuation in MRBD observed during the control trial, whereas PMBR was increased when submaximal contractions were performed in a fatigued state.
34

Zákonitosti rozdělení prudkých ochlazení v Česku a jejich příčiny / Regularities of the distribution of rapid cooling events in Czechia and their causis

Čašek, Matěj January 2020 (has links)
The diploma thesis deals with the topic of rapid day-to-day drops of air temperature. The research part of the thesis is focused on physical-geographical factors that affect the air temperature. Furthermore, the most common methods used to detect interdiurnal changes in air temperature are presented. Abrupt drops in air temperature were detected on the basis of the maximum and minimum daily air temperature at a total of 33 meteorological stations for the period from 1st January 1970 to 31st December 2019. The aim was to describe the regularities of the distribution of extreme drops in air temperature in both temperature characteristics, and to describe the influence of different physical-geographical conditions on the magnitude and seasonality of decline events. The thesis also describes the influence of the prevailing weather situation (according to HMÚ typing) on extreme decreases in both temperature characteristics. It was proved that the shape of the relief has a significant effect on the seasonality of decreases, especially the minimum air temperatures. Stations on convex relief are characterized by a more balanced distribution of these events during the year, while at stations on concave relief there are the largest decreases in the minimum air temperature, especially in winter. The influence...
35

Compensation in the Expropriation Act / Ersättning enligt expropriationslagen

Ljung, Alexander, Bernebrant, Daniel January 2013 (has links)
The purpose with this work is to investigate how much effect the value decrease following the expropriation has on the total compensation for acquisitions on expropriation grounds and the extent of acquisitions of entire properties where value decrease may have occurred. The value decrease originates from the business, which expropriation is made for. This value decrease is compensated in the influence rule in the Expropriation Act (1972:719). The reason value decrease has an impact on the total compensation is because no surcharge is given the compensation in the influence rule. While it three years ago was instituted a surcharge of 25% in the Expropriation Act (EA) for the compensation for the property's value at the acquisition date. The strongest reason for the introduction of the surcharge was to strengthen the property rights of property owners when their properties are acquired on expropriations purposes. But the difference in surcharge means that the compensation will be inconsistent, depending on whether the value decrease has occurred or not. The arising of the difference in total compensation has emerged from studies of the EA and its propositions. Furthermore, it emerges from the Environmental Code that properties acquired in its entirety as a result of environmental damage, i.e. activities that lead to damage to other properties, will also be compensated in the influence rule and thus no surcharge will be given. To investigate how many properties that have been acquired on expropriation purposes, where damage may have occurred and is compensated through the influence rule, there has been an empirical study of Trafikverket´s property acquisitions. Furthermore, Malmberget has been included in efforts to highlight the extent of land acquisition where properties may be subject to damages under the influence rule. In the empirical study, 166 properties acquired by Trafikverket in the past three years have been studied. 44 of these have been acquired for the construction of roads or railroads, whose activities may have resulted in a value decrease on the properties acquired. 122 properties were probably acquired as a result of environmental damage. Results from the study show that the influence rule might have been used in several acquisitions made in recent years and therefore had an impact on the total compensation. As the full compensation does not get the surcharge of 25%, the compensation as mentioned earlier becomes inconsistent. This does not seem reasonable when the motive behind the proposition was to strengthen the ownership. Thus, it should be the loss of the owner right that gets compensated and therefore the compensation through the influence rule also should be given the surcharge. / Syftet med detta arbete är att undersöka hur stor inverkan företagsskada kan ha på den totala ersättningen vid förvärv på expropriationsgrunder och i vilken omfattning förvärv av hela fastigheter, där företagsskada kan ha förekommit, har skett. Företagsskada är den värdeminskning en verksamhet, vilken expropriation sker för, leder till på fastighet som ska förvärvas. Denna skada ska ersättas enligt influensregeln i expropriationslagen (1972:719). Anledning till att företagsskada har påverkan på den totala ersättningen är att det inte utgår något påslag för ersättning enligt influensregeln, medan det för tre år sedan instiftades ett påslag om 25 % i expropriationslagen (ExL) för den ersättning som ska utgå för fastighetens värde vid förvärvstillfället. Det starkaste motivet till att införa detta påslag var att stärka äganderätten för fastighetsägare när deras fastigheter förvärvas på expropriationsgrunder. Skillnaden med påslaget kan leda till att ersättningen blir inkonsekvent, beroende på om företagsskada föreligger eller inte. Att det uppkommer en skillnad i den totala ersättningen har framkommit i studier av ExL och dess propositioner. Vidare framkommer det av miljöbalken att fastigheter som förvärvas i sin helhet till följd av miljöskada, d.v.s. verksamhet som leder till skada på annan fastighet, även denna ska ersättas enligt influensregeln och inte ges något påslag. För att undersöka hur många fastigheter som har förvärvats på expropriationsgrunder, där skada som ska ersättas enligt influensregeln kan ha uppkommit, har en empirisk studie av Trafikverkets fastighetsförvärv gjorts. Vidare har även Malmberget inkluderats i arbetet för att belysa omfattning av fastighetsförvärv där fastigheter kan vara utsatta för skada enligt influensregeln. I den empiriska studien har 166 fastigheter förvärvade av Trafikverket under de tre senaste åren undersökts. 44 styckena av dessa har förvärvats för att uppföra anläggning, vars verksamhet kan ha lett till företagsskada på förvärvad fastighet. 122 styckena har troligen förvärvats till följd av miljöskada. Resultatet från studien visar att influensregeln kan ha använts vid flertalet förvärv under de senaste åren och därför haft en påverkan på den totala ersättningen. I och med att ersättningen i sin helhet inte ges påslaget om 25 % blir ersättningen som tidigare nämnt inkonsekvent. Detta känns inte skäligt då det i propositionen framgår att det är äganderätten som ska stärkas. Således bör det vid förlorande av äganderätt, till följd av förvärv på expropriationsgrunder, utgå ett påslag även för ersättning som ska bestämmas enligt influensregeln.
36

Sastav, reakcije nastajanja i inhibicija stvaranja melanoidina u nečistim rastvorima saharoze / THE STRUCTURE, FORMING REACTION AND INHIBITION OF MELANOIDINS IN THE INPURE SUCROSE SOLUTIONS

Gyura Julianna 16 November 1992 (has links)
<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Nastajanje i inhibicija stvaranja melanoidina u nečistim rastvorima saharoze je ispitivana na uzorcima neafinisanog i afinisanog C produkta na 80 [&deg;C].</p><p>Utvrdjena je zavisnost obrazovanja bojenih materija tipa melanoidina od vremena reakcije, od sadržaja suve materije, kao i od sadržaja i vrste aminokiselina.<br />Smanjenje obojenosti rastvora zavisi od koncentracije natrikum-sulfita i matematički je definisano Baule-Mitscherlichovim krivama zasićenja. Maksimalni efekat odbojavanja koji se može postići iznosi 30 [%] na 560 [nm], odn. 20 [%] na 420 [nm], ne razlikuje se za rastvore neafinisanog i afinisanog C produkta, a ostaje nepromenjen u vremenu od 1620 [min].</p><p>Povećanje koncentracike vodonik-peroksida je praćeno porastom količine bojenih materija prevedenih u leuko oblike, i produžavanjem vremena oksidacije. U odsustvu slobodnog vodonik-peroksida dolazi do reverzije boje rastvora.<br />Smanjenje obojenosti rastvora neafinisanog i afinisanog C produkta je signifikantno veće pri uzastopnom delovanju oksidacionog i redukcionog sredstva od smanjenja obojenosti postignutog njihovim pojedinačnim delovanjem. Efekti uzajamnog delovanja se ne menjaju u ispitivanom vremenu.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>Reaction and inhibition of melanoidine formation in inpure solutions of sucrose were investigated on affinated and unaffinated C sugar samples carried out on 80 [&deg;C].<br />Melanoidin type colour formation dependending on reaction time, dry matter content and content and variety on amino acids has been studied.<br />Colour decrease in solutions depended on concentration of sodium sulphite and was mathematically defined by Baule-Mitscherlich curve of saturation. Maximum effect of colour decrease wich can be obtained was 30 [%] at 560 [nm], and 20 [%] at 420 [nm] wavelength respectively, and without any difference between affinated and unaffinated C sugar solutions, but it has stayed unchanged during reaction time of 1620 [min]. Hydrogen peroxide concentration rise was followed by increasing amounts of colour compounds transferred in leuco forms and by prolonged oxidation time. Absence of free hydrogen peroxide has induced the reverse formation of colour solutions.</p><p>Colour decrease in unaffinated and affinated C sugar solution was significantly larger, during subsequent treatment of oxidizing and reducing compounds, than during separate reactions. During reaction time the mutual treatment effect was unchangeable.</p>
37

The Role of Nucleotide Signaling in the Regulation of ICl,swell in Human 1321N1 Astrocytoma Cells

Wenker, Ian C. 08 May 2009 (has links)
No description available.
38

SCHEDULING SURGICAL CASES IN A CONSTRAINED ENVIRONMENT

Vijayakumar, Bharathwaj 19 April 2011 (has links)
No description available.
39

The Relative Security Metric of Information Systems: Using AIMD Algorithms

Owusu-Kesseh, Daniel 28 June 2016 (has links)
No description available.
40

Preventivní a kurativní využití kineziotapu při zatížení palce ruky v ambulantní terapeutické péči / Kinesio taping in treatment and prevention of thumb overload in outpatient physiotherapy

Neklanová, Anna January 2015 (has links)
Title : Kinesio taping in treatment and prevention of thumb overload in outpatient physiotherapy Purposes : The main purpose of this thesis was to evaluate a degree of pain decrease in thumb joint after kinesio tape application. The differences in grip strength were concurrently evaluated to objectify previous results. Hand dynamometer was used to support this claim. Methods : Data for the experiment were obtained by use of hand dynamometer measurement and record of a pain degree according to chosen pain scale. Each person was measured right before defined strain and immediately after it (daily work in outpatient therapy according to therapist's working shift). Each therapist was asked to record a degree of actual pain following the instructions during strain. All the results were processed and statistically analyzed. Results : The results show that kinesio tape is successful in decreasing of thumb joint pain. This was confirmed both during and after the strain. At the same time kinesio tape prevents decreasing of the grip strength. Keywords : Thumb, thumb joint, kinesio taping of a thumb, dynamometry, pain decrease of a thumb, overloading of a thumb

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