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Andingmen & deshengmen guanxiang urban boundary revitalizationChen, Xiwei 11 July 2013 (has links)
The master's design studio project is a semester-long design course focusing on
the methodologies and feasibilities to update the old city gates, walls and moats in
Beijing with hybridized infrastructure as catalyst to its surrounding area's urbanrenovation
process. With more and more emphasis on the re-construction of the
old city-structure in Beijing (city gates, city walls and Moats dated from Ming
Dynasty), its future urban design practice has become a critical topic. Study takes
Beijing Anding City Gate & Desheng City gate area, together with part of the moat
and city walls area linking those two gates as research object. / text
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Monolithic multiphysics simulation of hypersonic aerothermoelasticity using a hybridized discontinuous Galerkin methodEngland, William Paul 12 May 2023 (has links) (PDF)
This work presents implementation of a hybridized discontinuous Galerkin (DG) method for robust simulation of the hypersonic aerothermoelastic multiphysics system. Simulation of hypersonic vehicles requires accurate resolution of complex multiphysics interactions including the effects of high-speed turbulent flow, extreme heating, and vehicle deformation due to considerable pressure loads and thermal stresses. However, the state-of-the-art procedures for hypersonic aerothermoelasticity are comprised of low-fidelity approaches and partitioned coupling schemes. These approaches preclude robust design and analysis of hypersonic vehicles for a number of reasons. First, low-fidelity approaches limit their application to simple geometries and lack the ability to capture small scale flow features (e.g. turbulence, shocks, and boundary layers) which greatly degrades modeling robustness and solution accuracy. Second, partitioned coupling approaches can introduce considerable temporal and spatial inaccuracies which are not trivially remedied. In light of these barriers, we propose development of a monolithically-coupled hybridized DG approach to enable robust design and analysis of hypersonic vehicles with arbitrary geometries. Monolithic coupling methods implement a coupled multiphysics system as a single, or monolithic, equation system to be resolved by a single simulation approach. Further, monolithic approaches are free from the physical inaccuracies and instabilities imposed by partitioned approaches and enable time-accurate evolution of the coupled physics system. In this work, a DG method is considered due to its ability to accurately resolve second-order partial differential equations (PDEs) of all classes. We note that the hypersonic aerothermoelastic system is composed of PDEs of all three classes. Hybridized DG methods are specifically considered due to their exceptional computational efficiency compared to traditional DG methods. It is expected that our monolithic hybridized DG implementation of the hypersonic aerothermoelastic system will 1) provide the physical accuracy necessary to capture complex physical features, 2) be free from any spatial and temporal inaccuracies or instabilities inherent to partitioned coupling procedures, 3) represent a transition to high-fidelity simulation methods for hypersonic aerothermoelasticity, and 4) enable efficient analysis of hypersonic aerothermoelastic effects on arbitrary geometries.
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A SOM+ Diagnostic System for Network Intrusion DetectionLangin, Chester Louis 01 August 2011 (has links)
This research created a new theoretical Soft Computing (SC) hybridized network intrusion detection diagnostic system including complex hybridization of a 3D full color Self-Organizing Map (SOM), Artificial Immune System Danger Theory (AISDT), and a Fuzzy Inference System (FIS). This SOM+ diagnostic archetype includes newly defined intrusion types to facilitate diagnostic analysis, a descriptive computational model, and an Invisible Mobile Network Bridge (IMNB) to collect data, while maintaining compatibility with traditional packet analysis. This system is modular, multitaskable, scalable, intuitive, adaptable to quickly changing scenarios, and uses relatively few resources.
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Techno-economic analysis of innovative storage power plants utilizing existing CCGT systems : An Austrian case studyPöcklhofer, Niklas, Sares, Philipp January 2023 (has links)
Efforts to mitigate climate change and current geopolitical disruptions have revealed that changes to the existing energy system are urgently required to offer sustainable and secure energy for Europe. Hence, the role of conventional thermal power plants is being challenged and new technologies providing additional functionality for the power grid are pushing into the market. Thus, system perspectives and considerations of synergies between different technologies become more important. Current research efforts are focused on the hybridization of renewable technologies, sector coupling, and repurposing of existing energy infrastructure. Nevertheless, literature is still lacking a system perspective analysis of these combined topics. For this purpose, a case study on integrating the existing Mellach combined cycle gas turbine (CCGT) power plant into a hybrid energy system dominated by PV and wind power via hydrogen production facilities is performed. The performance of this innovative storage power plant (ISPP) is assessed through an optimization-based techno-economic-environmental analysis. Further, the sensitivity of such a system to external uncertainties such as the electricity price, component costs, or CO2 emission pricing is evaluated. Under the assumptions made, the retrofitting of the CCGT to be (co-)fired with hydrogen does not provide an economically feasible solution for repurposing the power plant. The results indicate that the highest revenues are obtained when natural gas firing in the CCGT is enabled. Simultaneously, this also causes the highest CO2 emissions. However, natural gas needs to be phased-out by 2030 to meet Austria’s climate target. Combining renewables with hydrogen-firing of the CCGT system or sales to the hydrogen market increases the system flexibility and resilience to external influences. However, the revenue streams from continuing the CCGT operation cannot offset the initial investment costs of the turbine upgrade. The investigated ISPP is subject to several uncertainties. Depending on the development of certain components or market properties, utilizing the existing power block through sector coupling with hydrogen can improve the system economics. Eventually, this can make the system profitable depending on the developments. The investigated system behavior shows an improved utilization of renewable energy by converting it into hydrogen instead of curtailing or selling the electricity at a low price. Hence, the investigated set of components is most profitable when the installed renewable energy capacity is a multiple of the maximum electric power of the existing CCGT power block. On the other hand, providing the option of blending natural gas with hydrogen is not economically beneficial under the assumptions made. Further, the results showed that an increase in EU ETS CO2 certificate prices would improve the profitability of the ISPP compared to the state-of-the-art operation with natural gas. Another finding of the analysis is the sensitivity of the hydrogen system to the electrolyzer cost. Meeting the near-term electrolyzer cost development target would significantly increase the optimal hydrogen system sizing, as well as the economic performance of the entire power plant. Additionally, the system can balance the power grid by operating the electrolyzer using grid electricity purchased at negative prices during hours of power oversupply, which is not possible in the existing configuration. It can be concluded that the investigated ISPP is more resilient to external influences given its enhanced operation flexibility and different revenue streams. / Bemötande av klimatförändringar och nuvarande geopolitiska störningar har avslöjat att förändringar av det befintliga energisystemet är nödvändiga för att erbjuda hållbar och säker energi för Europa. Därför ifrågasätts rollen för konventionella termiska kraftverk och nya teknologier som erbjuder ytterligare funktionalitet för elnätet gör sin inmarsch på marknaden. Därmed blir systemperspektiv och överväganden av synergier mellan olika teknologier allt viktigare. Aktuell forskning fokuserar på hybridisering av förnybara teknologier, sektorkoppling och omdaning av befintlig energiinfrastruktur. Trots detta saknas fortfarande en systemperspektivsanalys av dessa kombinerade ämnen i litteraturen. För detta ändamål genomförs en fallstudie om integrering av det befintliga kombikraftverket (CCGT) i Mellach i ett hybridenergisystem dominerat av sol- och vindkraft via vätgasproduktionsanläggningar. Prestandan för detta innovativa lagringskraftverk (ISPP) utvärderas genom en optimeringsbaserad teknisk-ekonomisk-miljömässig analys. Dessutom utvärderas känsligheten hos ett sådant system för externa osäkerheter som elpriset, komponentkostnader eller prissättning av koldioxidutsläpp. Under de antaganden som gjorts ger ombyggnaden av CCGT för att använda (co-)eldning med vätgas inte en ekonomiskt genomförbar lösning för omdaning av kraftverket. Resultaten indikerar att de högsta intäkterna uppnås när naturgaseldning i CCGT tillåts. Samtidigt orsakar detta också de högsta koldioxidutsläppen. Dock behöver naturgas fasas ut före 2030 för att uppnå Österrikes klimatmål. Att kombinera förnybara energikällor med vätgaseldning av CCGT-systemet eller försäljning till vätgasmarknaden ökar systemets flexibilitet och motståndskraft mot externa påverkan. Intäktsströmmarna från fortsatt drift av CCGT kan dock inte kompensera för de initiala investeringskostnaderna för uppgraderingen av turbinen. Det undersökta ISPP påverkas av flera osäkerheter. Beroende på utvecklingen av vissa komponenter eller marknadsegenskaper kan användningen av det befintliga kraftblocket genom sektorkoppling med vätgas förbättra systemekonomin. Slutligen kan detta göra systemet lönsamt beroende på utvecklingen. Det undersökta systembeteendet visar en förbättrad användning av förnybar energi genom att omvandla den till vätgas istället för att avbryta eller sälja el till ett lågt pris. Därför är det undersökta komponentsystemet mest lönsamt när den installerade kapaciteten för förnybar energi är flera gånger den maximala elektriska effekten hos det befintliga CCGT-kraftblocket. Å andra sidan är möjligheten att blanda naturgas med vätgas inte ekonomiskt fördelaktig under de antaganden som gjorts. Dessutom visade resultaten att en ökning av EU ETS-koldioxidcertifikatpriserna skulle förbättra lönsamheten för ISPP jämfört med dagens drift med naturgas. En annan slutsats från analysen är känsligheten hos vätgassystemet för elektrolysatorns kostnad. Att uppnå den närtidsmål för kostnadsutveckling för elektrolysatorn skulle signifikant öka den optimala storleken på vätgassystemet, liksom den ekonomiska prestandan för hela kraftverket. Dessutom kan systemet balansera elnätet genom att driva elektrolysatorn med el från elnätet som köps till negativa priser under timmar av överflödig kraft, vilket inte är möjligt i den befintliga konfigurationen. Slutsatsen är att det undersökta ISPP är mer motståndskraftigt mot externa påverkan med tanke på dess förbättrade driftflexibilitet och olika intäktsströmmar.
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Sufism and Politics among Senegalese Immigrants in Columbus, Ohio: Ndigel and the Voting Preferences of a Transnational CommunityCamara, Samba 12 June 2013 (has links)
No description available.
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