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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.
251

Teoretické využití nanotechnologie pro filtraci ve vzduchotechnice / Theoretical use of nanotechnology for filtration in HVAC systems

Bosák, Jan January 2016 (has links)
Thesis solves problems using the nanotechnology for air filtration in HVAC systems. Main specialization work is air filtration for clean spaces with high classes of purity. For example Hospitals, sophisticated technology service, pharmacy etc. Thesis is devide for three parts. First part contains foundation infromations about theory and making fabrics by nanotechnology. Next I described laws of physics, That were using during the solving filtration´s issues. Goal for second part was making the experiments, which should show abilities and properties nanofilters during the air filtration in real environment HVAC systems. In the end measure part is compare nanofilters with common filters. There is describe nanofiltres behavior and their possibilies during the filtration as well as. In last part I expressed own opinions on air filtration by nanofibers. Opinions were making throught informations, That I found out in the process working on thesis and my experiences in HVAC field. By this facts I did compare for get a better idea. Additionally last part contains summary infomations from previously parts and own vision to development in the future. Goal work isn´t promotion and advertising sorts technologies. Ask is just summary and describe discovered knowledges, considered opinions ensue from measuring, information from the Net and people Who work in nanotechnology field.
252

Hypervisor-based cloud anomaly detection using supervised learning techniques

Nwamuo, Onyekachi 23 January 2020 (has links)
Although cloud network flows are similar to conventional network flows in many ways, there are some major differences in their statistical characteristics. However, due to the lack of adequate public datasets, the proponents of many existing cloud intrusion detection systems (IDS) have relied on the DARPA dataset which was obtained by simulating a conventional network environment. In the current thesis, we show empirically that the DARPA dataset by failing to meet important statistical characteristics of real-world cloud traffic data centers is inadequate for evaluating cloud IDS. We analyze, as an alternative, a new public dataset collected through cooperation between our lab and a non-profit cloud service provider, which contains benign data and a wide variety of attack data. Furthermore, we present a new hypervisor-based cloud IDS using an instance-oriented feature model and supervised machine learning techniques. We investigate 3 different classifiers: Logistic Regression (LR), Random Forest (RF), and Support Vector Machine (SVM) algorithms. Experimental evaluation on a diversified dataset yields a detection rate of 92.08% and a false-positive rate of 1.49% for the random forest, the best performing of the three classifiers. / Graduate
253

Agronomic Suitability Studies in the Russian Altai Using Remote Sensing and GIS: Untersuchungen der Landwirtschaftseignung im Russischen Altai unter Verwendung von Fernerkundungsdaten und GIS

Kelgenbaeva, Kamilya 18 December 2007 (has links)
The doctoral thesis describes methodologies and appropriate adaptations of existing solutions to model land suitability in two ways for the valley and basin areas of the South-Siberian Altai Mountains within a geo-information system (GIS) environment. Starting-point approaches are: 1) the Agricultural Soil Suitability Model „Almagra” and Land Capability Model “Cervatana”/MicroLEIS System (De la Rosa et. al 1992, 1998) developed for Mediterranean regions and a method specifically compiled by Burlakova L. M. (1988) for the Altai based on the weighted means of a factor set. 2) For comparison purposes, second, third and fourth versions of the same model are developed using three different types of Fuzzy Logic approaches. They are used to present how Gauss membership functions of particular classes can be computed as different classes and how variables taking values in ranges can be handled in a mathematical way. Furthermore, the paper presents ideas on how remote sensing might interact with the geo-information system (GIS) where - like in the present case – the required input geo-data are not fully sufficient to (i) feed the models formalising soil and climatic conditions, and (ii) to characterise the patterns of land management within the study area. Three agricultural crops (summer wheat, sunflowers and potatoes) are relevant to the Altai Region at a regional level and are, therefore considered. A rating is classified using five suitability classes according to the FAO classification (1976). For the case study the Uimon Basin was chosen. Social and economic factors are so far excluded but can be added within a further phase of development. / Diese Doktorarbeit beschreibt Methoden und geeignete Anpassungen bereits existierender Lösungen, um auf zwei verschiedenen Wegen die Landeignung für die Tal- und Beckenregionen der Südsibirischen Altaigebirges innerhalb eines Geoinformationssystems zu modellieren (GIS). Die Ausgangsmethoden sind: 1) die Bodeneignungsmodelle „Almagra" and „Cervatana“ (MicroLEIS System), entwickelt für die Mittelmeerregionen (De la Rosa et al. 1992 and 1998) und die „Gewichtsmethode“, welche Burlakova L. M. (1988) speziell für die Altairegion entwickelte. Letztgenannte Methode basiert auf den gewichteten Mitteln für eine gegebene Anzahl von Faktoren. 2) Zum Vergleich, die zweite, dritte und vierte Version des gleichen Modells mit drei unterschiedlichen Typen wurden mit Fuzzy-Logik-Methoden entwickelt. Sie werden benutzt, um darzustellen, wie unscharfe Mengen zum einen die Berechnung von Gauß-Mitgliedschaftsfunktionen bestimmter Klassen veranschaulichen können, welche zu anderen Klassen gehören, und wie die Variablen in einer mathematischen Handhabung angefasst werden können. Außerdem stellt diese Arbeit Ideen vor, wie die Fernerkundung das Geoinformationssystem (GIS) eingesetzt werden kann, wenn - wie im vorliegenden Fall - nur unzureichend Geodaten vorhanden sind, (i) um in die Modellierung der Boden- und Klimabedingungen einzugehen und (ii) um die Charakteristik des Landmanagements im Untersuchungsgebiet zu kennzeichnen. Drei landwirtschaftliche Agrarkulturen (Sommerweizen, Sonnenblumen und Kartoffeln) sind für die Altairegion auf regionaler Ebene von Bedeutung und wurden daher in die vorliegende Untersuchung einbezogen. Die Bewertung erfolgte nach fünf Eignungskategorien, entsprechend der FAO Klassifikation (1976). Das Uimon-Becken wurde als Untersuchungsgebiet ausgewählt. Soziale und ökonomische Faktoren wurden bisher ausgeschlossen, können aber innerhalb einer weiteren Entwicklungsphase hinzugenommen werden.
254

Proračun intenziteta erozije zemljišta u Polimlju (Crna Gora i Srbija) i Širindareh slivu (Iran) korišćenjem WIntErO modela / Calculation of soil erosion intensity in Polimlje (Montenegro and Serbia) and Širindareh basin (Iran) using the WIntErO model

Vujačić Duško 10 April 2019 (has links)
<p>Predmet&nbsp; ovog&nbsp; rada&nbsp; predstavlja&nbsp; geografski prostor&nbsp; sliva&nbsp; Lima&nbsp; od&nbsp; Plavskog&nbsp; jezera&nbsp; do&nbsp; brane&nbsp; HE &#39;&#39;Potpeć&#39;&#39;,&nbsp; kao&nbsp; jedne&nbsp; prostorno-funkcionalne&nbsp; cjeline,koji&nbsp; se&nbsp; prostire&nbsp; na&nbsp; teritorijama&nbsp; država&nbsp; Crne&nbsp; Gore (2334&nbsp; km <sup>2</sup>),&nbsp; Srbije&nbsp; (2407,7&nbsp; km <sup>2</sup> )&nbsp; i&nbsp; Albanije&nbsp; (115,5<br />km <sup>2 </sup>) i &Scaron;irindareh sliv na NE Irana.Kori&scaron;ćenjem&nbsp; računarsko-grafičkog&nbsp; metoda<br />programa&nbsp; &quot;WintErO&quot;,&nbsp; u&nbsp; proučavanju&nbsp; oticanja&nbsp; i intenziteta&nbsp; erozije,&nbsp; vrijednosti&nbsp; povr&scaron;ina&nbsp; (povr&scaron;ina slivova,&nbsp; povr&scaron;ina&nbsp; između&nbsp; izohipsi&nbsp; i&nbsp; sl.)&nbsp; i&nbsp; dužina,&nbsp; tj.rastojanja sa karte (dužina glavnog vodotoka, dužina linije vododjelnice i sl.) veoma precizno je obrađena,<br />&scaron;to&nbsp; nije&nbsp; uvijek&nbsp; bio&nbsp; slučaj&nbsp; kod&nbsp; primjene&nbsp; mehaničkih instrumenata,&nbsp; planimetara&nbsp; i&nbsp; kurvimetra.&nbsp; Obradom dobijenih&nbsp; fizičko-geografskih&nbsp; inputa,&nbsp; nakon&nbsp; unosa podataka,&nbsp; dobijeni&nbsp; su&nbsp; rezultati.&nbsp; Detaljan&nbsp; prikaz&nbsp; ove računarsko&nbsp; grafičke&nbsp; metode&nbsp; predstavljen&nbsp; je&nbsp; u rezultatima ove doktorske disertacije.<br />Dio istraživanja ovog doktorskog rada obavljen je na području sjeveroistoka Irana, u slivu &Scaron;irindareh. Oko 100 miliona hektara iranske teritorije je izloženo eroziji&nbsp; ili&nbsp; drugim&nbsp; hemijskih&nbsp; i&nbsp; fizičkih&nbsp; degradacija.Erozija&nbsp; vodom&nbsp; ugoržava&nbsp; velike&nbsp; povr&scaron;ine&nbsp; u&nbsp; Iranu,<br />uni&scaron;tavajući pri tom plodna poljoprivredna zemlji&scaron;ta. Skoro&nbsp; 35&nbsp; miliona&nbsp; hektara&nbsp; Irana&nbsp; je&nbsp; pod&nbsp; uticajem različitih&nbsp; vrsta&nbsp; erozije&nbsp; vodom.&nbsp; Ova&nbsp; činjenica&nbsp; je&nbsp; bila povod i izazov da se i ova istraživanja dijelom osvrnu na&nbsp; ovu&nbsp; problematiku&nbsp; u&nbsp; Iranu,&nbsp; testirajući&nbsp; pri&nbsp; tom<br />novopripemljeni&nbsp; model&nbsp; WIntErO&nbsp; na&nbsp; jednom&nbsp; od slivova u Iranu.</p> / <p>The subject of this paper is the&nbsp; geographical area of&nbsp; the Lim&nbsp; Basin&nbsp; from&nbsp; Plav&nbsp; Lake&nbsp; to&nbsp; the&nbsp; dam&nbsp; &quot;Potpeć&quot;,&nbsp; as&nbsp; a spatial-functional&nbsp; unit,&nbsp; spreading&nbsp; in&nbsp; the&nbsp; territories&nbsp; of&nbsp; the countries&nbsp; of&nbsp; Montenegro&nbsp; (2,334&nbsp; km2),&nbsp; Serbia&nbsp; (2407,7 km2)&nbsp; and&nbsp; Albania&nbsp; 115.5&nbsp; km2).&nbsp; In&nbsp; mathematicalgeographical terms,&nbsp; the research area is between 42 &deg; 37 &#39;and 43 &deg; 30&#39; north latitude and 17 &deg; 10 &#39;and 17 &deg; 23&#39; east longitude.&nbsp; The&nbsp; research&nbsp; area&nbsp; is&nbsp; located&nbsp; in&nbsp; the&nbsp; north&nbsp; of Albania,&nbsp; east&nbsp; and&nbsp; north-east&nbsp; of&nbsp; Montenegro,&nbsp; and&nbsp; in&nbsp; the southwest of Serbia. Using the computer-graphic&nbsp; method of the &quot;WintErO&quot; program, in the study of the erosion and intensity&nbsp; of&nbsp; erosion,&nbsp; the&nbsp; surface&nbsp; values&nbsp; (surface&nbsp; of&nbsp; the basins,&nbsp; the&nbsp; area&nbsp; between&nbsp; isohipins,&nbsp; etc.)&nbsp; and&nbsp; length,&nbsp; The distance&nbsp; from&nbsp; the&nbsp; map&nbsp; (the&nbsp; length&nbsp; of&nbsp; the&nbsp; main watercourse, the length of the line of the water line, etc.) is&nbsp; very&nbsp; precisely&nbsp; processed,&nbsp; which&nbsp; was&nbsp; not&nbsp; always&nbsp; the case with the use of mechanical instruments, planimeters and&nbsp; curvimeters.&nbsp; By&nbsp; obtaining&nbsp; the&nbsp; obtained&nbsp; physicalgeographic&nbsp; inputs,&nbsp; after&nbsp; entering&nbsp; the&nbsp; data,&nbsp; results&nbsp; were obtained.&nbsp; A&nbsp; detailed&nbsp; view&nbsp; of&nbsp; this&nbsp; computer&nbsp; graphic method&nbsp; is&nbsp; presented&nbsp; in&nbsp; the&nbsp; results&nbsp; of&nbsp; this&nbsp; doctoral dissertation.&nbsp; Part&nbsp; of&nbsp; the&nbsp; research&nbsp; of&nbsp; this&nbsp; doctoral&nbsp; thesis was&nbsp; done&nbsp; in&nbsp; the&nbsp; area&nbsp; of&nbsp; the&nbsp; northeast&nbsp; of&nbsp; Iran,&nbsp; in&nbsp; the Shirindareh basin. About 100 million hectares of Iranian territory are exposed to erosion or other types of chemical and&nbsp; physical&nbsp; degradation&nbsp; (Kheirodin,&nbsp; 2016).&nbsp; Erosion&nbsp; by water&nbsp; entangles&nbsp; large&nbsp; areas&nbsp; in&nbsp; Iran,&nbsp; destroying&nbsp; fertile agricultural&nbsp; land&nbsp; (Sadeghi,&nbsp; 2017).&nbsp; Almost&nbsp; 35&nbsp; million hectares of Iran&nbsp; are under the influence of various types of&nbsp; water&nbsp; erosion&nbsp; (Zakerinejad&nbsp; and&nbsp; Maerker,&nbsp; 2015).&nbsp; This fact&nbsp; was&nbsp; also&nbsp; a&nbsp; cause&nbsp; and&nbsp; challenge&nbsp; for&nbsp; the&nbsp; research&nbsp; to partly look at this issue in Iran, testing the new WIntErO model on one of the basins in Iran.</p>
255

Understanding Quadratic Functions Using Real World Problems and IT

Karim, Nakhshin A. 02 May 2012 (has links)
The concept of function is crucial to a great extent in modern mathematics and is considered a major barrier to many mathematics students. Students have difficulty interpreting information related to functions in general, and quadratic functions in particular. Quadratic Function is one of the topics which are covered in a course which is compulsory for a large number of students in the General Education Program of Zayed University. This program leads to different majors, including Mathematics Education, Business, Information Technology, and other majors. The challenge in teaching Quadratic Function in a course like this is mostly based on the fact that many students think that Quadratic Function is a difficult topic to understand and learn, and some teachers would agree with them that it is difficult to teach. In this paper, I demonstrate real world problems aimed to improve the students understanding of Quadratic Functions; life problems on this topic support developing student’s knowledge, critical thinking, quantitative reasoning, and analytical skills. This paper also includes examples of the techniques used with graphing of quadratic function, the algebra, and inverses of the same function. International move to improve mathematics curriculum have supported new goals for student’s learning which highlights problem solving skills, reasoning, ability to work in groups and individually, and use of technology. Knowing that information technology plays considerable role in achieving the above goals, teaching students the concept of Quadratic Functions can be smoothly achieved by using Information Technology in solving real world problems.
256

Confidence in the Use of Technology of Low-Income First-Year College Students' Retention

Hudson, Irene Marie 01 January 2018 (has links)
Compared to their peers, low-income students are 90% less likely to graduate within 6 years and are more likely to drop out. At the local site, this problem is also evident in that the retention rate for the Fall 2014-15 cohort was 78.3%, but just 60.2% for those defined as low-income students. The purpose of this study was to gain a better understanding of low-income 1st year college students' perceived confidence in their use of technology and how it influenced their decision to stay in college. Understanding the role technology plays in the decision to stay in college will shed light on ways to offer support to increase retention of these students. The conceptual framework that guided the study was Bruno's confidence based learning methodology. This framework suggests there is a connection between knowledge and confidence. A qualitative descriptive design was used collecting data through a series of 10 open-ended interviews with low-income 1st year college students. The central research question explored how low-income 1st year college students describe their confidence in the use of technology as a factor in their retention. Data analysis consisted of manual coding to identify themes from the interview data. The findings suggested low-income 1st year students do not have confidence in their ability to use technology and remain in college. A policy recommendation to reinstate the information literacy policy for low-income 1st year students could affect social change as additional resources help to raise low-income 1st year college students' confidence using technology and supports them to persist in college.
257

Pince optique et microscopie à contraste de phase pour l'étude de la mécanique cellulaire : développement, modélisation et calibration en réflexion. / Optical tweezers and phase contrast microscopy for the study of cell mechanics : experimental setup, modeling and calibration using backscattered light.

Gillant, Flavie 13 December 2016 (has links)
Ce manuscrit détaille le développement d'un montage de pince optique permettant d'étudier les propriétés mécaniques des cellules endothéliales, impliquées dans le développement de l'athérosclérose. Le but est de déterminer les propriétés viscoélastiques des cellules, et de suivre la propagation d’une contrainte mécanique au sein de la cellule. Cette contrainte mécanique est appliquée via une bille liée à la membrane de la cellule et soumise à un piège optique.Le dispositif réalisé combine le piégeage optique et la microscopie à contraste de phase, permettant d'exercer une force tout en imageant les cellules via le même objectif de microscope. L'originalité du montage de pince optique repose sur la détection du signal rétrodiffusé par la bille piégée, dans un plan conjugué du plan focal arrière de l'objectif, afin de mesurer la position relative de la bille par rapport au piège.Une part importante de ce travail a consisté à comprendre l'allure du signal détecté présentant un système d'interférences en anneaux, et à l’expliquer par un modèle simple. Ce modèle a permis de comprendre la présence d’artefacts de mesure de position dus à la superposition de l'anneau de phase sur la figure d’interférence. Pour y remédier, l'anneau de phase est déporté dans un plan conjugué intervenant uniquement dans l'imagerie de l'échantillon.La figure d'interférence présente un atout majeur : elle donne accès à la hauteur précise de la bille piégée, généralement difficile à mesurer. Cette information est nécessaire pour calibrer la constante de raideur du piège optique à la hauteur des cellules, que ce soit par l'analyse de la densité spectrale de puissance du mouvement brownien de la bille piégée ou par sa réponse à un échelon de position du piège. Ces deux méthodes de calibration, ainsi que l'application du théorème d’équipartition et l'analyse par inférence bayésienne, ont été mises en œuvre. Tous les résultats s'avèrent en bon accord. La calibration complète du dispositif en fait un outil prêt à l'emploi pour exercer des forces locales contrôlées en direction et en amplitude sur les cellules. / This manuscript details the development of an optical tweezer setup to study the mechanical properties of endothelial cells, involved in the development of atherosclerosis. The goal is to determine the viscoelastic properties of the cells, and to follow the propagation of the mechanical constraint inside the cell. This mechanical constraint is applied via a bead attached to the cell membrane and subjected to an optical trap.The setup built combines optical trapping with phase contrast microscopy, to apply a force while imaging the cells with the same microscope objective. The originality of the optical tweezer setup relies on the detection of the signal backscattered by the trapped bead, in a plane conjugate to the back focal plane of the objective, in order to measure the relative position of the bead with respect to the center of the trap.An important part of this work was dedicated to the understanding of the detected signal presenting an interference pattern with rings, explained by a simple model. This model provides an explanation for the position measurement artifacts arising from the superposition of the phase ring and the interference pattern. To solve the problem, the phase ring was moved in a conjugate plane involved only in the imaging path of the sample.The interference pattern has the main advantage of giving access to the precise height of the trapped bead, usually difficult to measure. This information is necessary to calibrate the optical trap stiffness at the height of the cells, either by the power spectrum analysis of the Brownian motion of the trapped bead, or by its response to a step motion of the trap. These two calibration methods, along with the application of the equipartition theorem and Bayesian inference analysis, were implemented and their results compared, showing a good agreement. The complete calibration of the setup makes it a ready-to-use tool to exert local forces controlled in direction and amplitude on cells.
258

"Om någon i ens ålder inte har TikTok så tycker man att den är lite konstig" : En kvalitativ utforskande studie kring TikToks inflytande på ungdomars totala medieanvändning

Wernersson, Wilma, Hummelstedt, Viktoria January 2021 (has links)
The main purpose of this essay is to investigate the role of teachers of religious education in the proactive work against violent extremism and radicalization. Furthermore, the ambition is to raise awareness of how these five teachers of religious education in the Swedish upper secondary schools and primary schools in the subject of religious studies work with and implement the school's democratic mission, and to find structures to teach about radicalization,fundamentalism, pro-violence extremism and terrorism. To obtain a result, five semi-structured interviews with active religious education teachers in the upper secondary schools and theprimary schools were conducted. To show the extent to which the school's democratic mission in the proactive work against radicalization and violent extremism is carried out, the collected empirical material has been analyzed based on Paulo Freire's awareness-raising pedagogy as a theoretical framework which indicates whether the interviewed teachers of religious education work according to what Freire calls the bank view or the liberating teaching. The study shows that all interviewed teachers work according to both these models. The teachers believe that it is inevitable to ignore the teaching of facts but prefer the liberating teaching. This is because all interviewed teachers believe that through dialogues and discussions, a critical thinking is created in the students.Furthermore, it appears that all teachers find it essential to create a good and open classroom climate where there is mutual acceptance of dissent. Thus, a long-term effort to create students as source-critical thinkers is fundamental.
259

Energikartläggning och energieffektivisering av flerbostadshus : Utredning av möjliga energibesparande åtgärdsplaner i området Oxhagen, Örebro.

Gunnarsson, John, Wallberg, Ida January 2022 (has links)
The purpose of this report is to investigate how Örebrobostäder (ÖBO) can decrease their energy use in the residential area of Oxhagen. Oxhagen is as mentioned a residential area located west from Örebro center and have about 690 apartments in different sizes. ÖBO needs to do this survey because they obey from the law of energy mapping in large companies, this law is produced from the EU directive, energy efficiency directive with its purpose to reduce the energy using in the country so the imported energy decreases. Energy statistics have been handed from ÖBO, this energy data has been analyzed and the data have been put in respective calculations, using Excel. Also, a model of a real estate has been made in the simulation program IDA ICE, in this simulation program energy calculations are made. There has also been a technical inspection of the reference real estate. The result shows that the biggest decrease in energy will happen with a decrease in the heating of the building. It also shows that a change of windows can reduce energy use significantly. Therefor the conclusion is that a combination of heat decrease, and window change can make an enormous difference in energy using for the reference real estate and the combination can also apply on other real estate in the area Oxhagen.
260

Harmonizace melodie / Melody Harmonization

Svoboda, Jan Unknown Date (has links)
The Master's Thesis discusses the possibilities of automatic melody harmonization. System use dictionary method for harmonization, this was inspired with comprimation algorithm LZW. System's output file is in MusicXML format.

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