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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.
411

Hybrid Broadband Ground-Motion Simulation Using Scenario Earthquakes for the Istanbul Area

Reshi, Owais A. 13 April 2016 (has links)
Seismic design, analysis and retrofitting of structures demand an intensive assessment of potential ground motions in seismically active regions. Peak ground motions and frequency content of seismic excitations effectively influence the behavior of structures. In regions of sparse ground motion records, ground-motion simulations provide the synthetic seismic records, which not only provide insight into the mechanisms of earthquakes but also help in improving some aspects of earthquake engineering. Broadband ground-motion simulation methods typically utilize physics-based modeling of source and path effects at low frequencies coupled with high frequency semi-stochastic methods. I apply the hybrid simulation method by Mai et al. (2010) to model several scenario earthquakes in the Marmara Sea, an area of high seismic hazard. Simulated ground motions were generated at 75 stations using systematically calibrated model parameters. The region-specific source, path and site model parameters were calibrated by simulating a Mw4.1 Marmara Sea earthquake that occurred on November 16, 2015 on the fault segment in the vicinity of Istanbul. The calibrated parameters were then used to simulate the scenario earthquakes with magnitudes Mw6.0, Mw6.25, Mw6.5 and Mw6.75 over the Marmara Sea fault. Effects of fault geometry, hypocenter location, slip distribution and rupture propagation were thoroughly studied to understand variability in ground motions. A rigorous analysis of waveforms reveal that these parameters are critical for determining the behavior of ground motions especially in the near-field. Comparison of simulated ground motion intensities with ground-motion prediction quations indicates the need of development of the region-specific ground-motion prediction equation for Istanbul area. Peak ground motion maps are presented to illustrate the shaking in the Istanbul area due to the scenario earthquakes. The southern part of Istanbul including Princes Islands show high amplitudes of shaking. The study serves as a step towards dynamic risk quantification for the Istanbul area that integrates physics based ground-motion simulations into an innovative dynamic exposure model to quantify risk.
412

The Control and Visualization of Intermolecular Interactions in Self-Assembly: From Star-Like and Dendron-Like Ionic Hybrid Macromolecules to Biomolecules

Sun, Xinyu 30 April 2021 (has links)
No description available.
413

Strategie NATO odstrašování: příčiny nedostatků při konfrontaci s ruskou hybridní strategií / NATO's Deterrence strategy: causes of shortcomings when facing Russian hybrid strategy

Ellis, Joseph January 2021 (has links)
The Relationship between Russia and NATO is a subject which finds itself continuously popular and relevant throughout discussion of international security. Yet, there is relatively large disagreements on how a conflict between the two actors would play out and how strong their given strategies are, in this case being how successful or strong should NATO's deterrence strategy be considered. Due to this, this paper will explore the main point of: What are the causes or reasonings behind the shortcomings of NATO deterrence strategy when facing a Russian Hybrid Strategy? In order to explore this, a deeper look is undertaken into the strengths of weaknesses behind both Russian and NATO capabilities and credibility within their given strategies. Furthermore, the primary region which will be explored within the relationship between Russia and NATO is that of the Baltic states, as this is the most likely area which NATO's deterrence strategy will be tested by Russian hybrid Warfare. This exploration will use qualitative studies along with wargaming scenarios which take into account the joint hybrid and conventional nature of Russia's hybrid strategy. Through this analysis, several causes of shortcomings are identified. These causes are the weakness derived from the chosen deterrence theory model undertaken...
414

Design remorkéru / Design of tugboat

Morcinek, Lukáš January 2016 (has links)
The topic of this diploma thesis is design of a tugboat. The thesis concerns designing a tugboat while meeting basic technological, ergonomic, ecologic and aesthetic requirements while using modern technologies and manufacturing options. There is an emphasis on innovative and unconventional solution, which will differ from contemporary products.
415

Legitimationskrav i fritidshem : Fritidslärares beskrivningar av legitimationskravets roll - en kvalitativ intervjustuide kring fritidslärares yrkesidentitet, dess roll och status. / Leisure-time teachers´descriptions of the role of the certification requirement : Qualitative interview inquiry concerning leisure-time teachers´professional identity, its role and status

Krasniqi, Mergim January 2021 (has links)
Denna studie har undersökt hur fritidslärare tolkar och beskriver legitimationskravets roll. Frågeställningarna har hjälpt studiens syfte i meningen att de har undersökt hur fritidslärare beskriver legitimationskravets roll för yrkesidentiteten, rollen legitimationskravet får i relation till andra yrkesgrupper på skolan och vad den får för roll i en fritidspedagogisk praktik. För att undersöka hur fritidslärare uppfattar legitimationskravet i relation till perspektiven ovan har studien använt sig av teoretiska utgångspunkten symbolisk interaktionism i samband med metodologiska ramverket grounded theory. Teorin och metoden har sammansatt försökt bena ut fritidslärares resonemang om legitimationskravet i relation till det dubbla uppdraget, möten med yrkesgrupper på skolan och kravets betydelse i en fritidspedagogisk praktik. Resultatet visar att legitimationskravets roll i relation till det dubbla uppdraget, möten med signifikanta andra och i en fritidspedagogisk praktik, tolkas väldigt olika. Några fritidslärare anser legitimationskravet förskjuter de in i skolans värld och lämnar fritidshemmet bakom sig, vilket i betydelse då innebär att skolan gagnas av införandet, inte fritidshemmet. Resultat visar också fritidslärare som upplever införandet som nästa statusklättrande steg i syfte att hamna i jämvikt med lärare på skolan, i syfte att bryta den underdogposition många fritidslärare upplever gentemot lärare.
416

Porozumění hybridní válce na Ukrajině: význam domácí zkušenosti / Understanding of hybrid warfare in Ukraine: to what extent this understanding is shaped by its internal experience?

Demyanchuk, Tetyana January 2019 (has links)
CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of Political Studies Department of Security Studies Master thesis 2019 Tetyana Demyanchuk CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of Political Studies Department of Security Studies Tetyana Demyanchuk Understanding of hybrid warfare in Ukraine: to what extent this understanding is shaped by its internal experience? Master thesis Prague 2019 Author: Tetyana Demyanchuk Supervisor: Mgr. Tomáš Kučera, Ph.D. Academic year: 2018/2019 Bibliographic note DEMYANCHUK, Tetyana (2019) Understanding of hybrid warfare in Ukraine: to what extent this understanding is shaped by its internal experience? 50 p. Master thesis. Charles University, Faculty of Social Sciences, Institute of Security Studies. Mgr. Tomáš Kučera, Ph.D. Abstract Hybrid warfare has achieved notoriety of being a buzzword attempting to explain the changes in the modern warfare that blur the lines between war and peace, conventional and irregular warfare. Despite its definitional shortcomings, it made its way into the official discourse of the politicians commenting on the conflict in Ukraine and Russia's involvement in it, which did not add clarity. This thesis aims to bring a Ukrainian perspective to the discussion, and it attempts to provide a deep interpretation of sufficiently...
417

Experimental Investigation of N2O/O2 Mixtures as Volumetrically Efficient Oxidizers for Small Spacecraft Hybrid Propulsion Systems

Stoddard, Rob L. 01 December 2019 (has links)
A hybrid thruster system utilizes propellants in two different stages, traditionally a solid fuel and a gaseous or liquid oxidizer. Recently hybrid thrusters have become a popular topic of research due to the high demand of a ”green” replacement for hydrazine. Not only are hybrid thruster systems typically much safer than hydrazine, but they are also a low-cost system with a high reliability in performance. The Propulsion Research Laboratory (PRL) at Utah State University (USU) has developed a hybrid thruster system using 3-D printed acrylonitrile butadiene styrene (ABS) as the fuel and gaseous oxygen (GOX) as the oxidizer. This system has been spaceflight flown and tested in a hard vacuum environment with success. However, GOX has a low density and must be stored at high pressures to be considered viable. This thesis investigates the use of N2O/O2 mixtures, ”Nytrox”, and more commonly known as ”laughing gas”, as a higher density replacement oxidizer for GOX. Ina manner directly analogous to the creation of soda-water using dissolved carbon dioxide, Nytrox is created by bubbling gaseous oxygen under high pressure into nitrous oxide until the solution reaches saturation level. Oxygen in the mixture ullage dilutes the nitrous oxide vapor, and increases the required decomposition activation energy of the fluid by several orders of magnitude. Data from tests using each oxidizer are analyzed and presented for performance comparisons. Comparisons include, ignition reliability, ignition energy, thrust coefficient, characteristic velocity, specific impulse, and regression rate. Nytrox is shown to work effectively as a “drop in” replacement for gaseous oxygen, exhibiting slightly reduced specific impulse and regression rate, but with the trade of a significantly higher volumetric efficiency.
418

It's Not Fusion: Hybridity in the Music of Vijay Iyer and Rudresh Mahanthappa

Govind, Arathi 12 1900 (has links)
This thesis concerns the performance of identity in the music of Indian American jazz musicians Rudresh Mahanthappa and Vijay Iyer. In combining the use of Indian classical music elements with jazz, Iyer and Mahanthappa create music that is inextricably tied to their multifaceted identities. Traditional musicological analysis is juxtaposed with a theoretical framework that draws on postcolonial theory and the history of Asian immigrant populations to the U.S. I chronicle the interactions between Indian and Western music and link it to larger issues of Asian American identity formation and activism through music. Through interviews and transcriptions of studio recordings, I identify specific compositional and improvisational strategies of the musicians. I emphasize the role of individual agency in the formation of second-generation identities, drawing attention to the distinct ways that Iyer and Mahanthappa approach their music. Finally, I connect this research to a larger discourse on Indian American artistic identity.
419

Impact of a Hybrid Storage Framework Containing Battery and Supercapacitor on Uncertain Output of Wind and Solar Power Systems

K C, Bibek 01 December 2019 (has links)
Renewable energy resources (RES) are becoming more popular for electricity generation due to their easy installation, flexibility, low cost, environmental compatibility, etc. However, their fluctuating nature is a major drawback, which decreases the power quality and makes them less trusty in the power system. To mitigate this problem, battery energy storage (BES) has been widely used with renewable energy sources. Because batteries are designed to handle “steady fluctuations” of power, the “sudden and peak” fluctuating power levels of renewable energy sources may cause shorter life spans for them, which may cause dramatic economic loss or negatively impact the power quality. Also, even though batteries have been used as a backup for RES, high power quality cannot be guaranteed when there is a rapid and peak fluctuations on source/load.
420

Medarbetarskap i en hybrid arbetsmiljö : En fallstudie om ledares anpassning för att främja medarbetarskap

Rikner, William, Neijman, Daniel January 2022 (has links)
Pandemin som bröt ut till följd av covid-19 var till stor del startskottet för organisationer att börja använda virtuella verktyg i en större grad för att kunna arbeta i fler arbetsmiljöer än i endast den traditionella, vilket har varit i organisationens lokaler. Många organisationer har genom det till viss del påtvingade bytet till den virtuella arbetsmiljön upptäckt att det finns många möjligheter med denna flexibilitet som de i framtiden vill fortsätta att nyttja. Vanligt är att organisationer övergår till en lösning där de vill försöka utnyttja fördelarna med respektive arbetsmiljö genom att kombinera arbete i organisationens lokaler med arbete på andra platser i en hybrid arbetsmiljö. Skiftet till en ny typ av arbetsplats medför många förändringar för både ledare och medarbetare inom organisationer. Ledarskap förändras ständigt och den mer moderna synen på olika typer av ledarskap skiljer sig gentemot mer traditionella synsätt där ledarskap ofta förknippas med att ge order och inneha auktoritet. Medarbetare i mer moderna synsätt på ledarskap innehar större frihet och förväntas ta mer ansvar i sina arbetsroller, vilket är starkt förknippat med medarbetarskap. Precis som mycket annat inom organisationer påverkas av ett byte av arbetsmiljö, så görs även ledarskap och medarbetarskap det och behöver anpassas därefter. Studien har besvarat denna problemformulering, det vill säga hur ledarskap kan anpassas i en hybrid arbetsmiljö för att främja medarbetarskap. Denna problemformulering har besvarats med hjälp av 12 intervjuer med medarbetare och ledare inom en organisation som har gått från arbete i organisationens lokaler, via hemarbete under två år, till att i framtiden bedriva arbete i en hybrid arbetsmiljö. Resultatet visade att ledarskapet på en generell nivå behöver anpassas för att främja medarbetarskap vid en övergång till en hybrid arbetsmiljö, men att behovet av anpassning skiljer sig åt utifrån kontextuella skillnader och förutsättningar. Vissa delar av medarbetarskapet kräver en större anpassning från ledarens sida för att ge samma utfall i en hybrid arbetsmiljö, medan vissa moment och processer kan genomföras på liknande sätt även i en hybrid arbetsmiljö.

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