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Safe Haven Assets During the COVID-19 Pandemic : a study of safe haven aspects of gold and Bitcoin in U.S. financial marketsMelin, Erik, Pettersson, Albert January 2022 (has links)
This paper explores the possibility of gold and Bitcoin acting as safe haven investments during the Corona pandemic. To answer the research question the authors use OLS-, GARCH-, and TGARCH-models. The S&P 500 stock- and S&P U.S. Aggregate bond-indexes are used as a measure of the performance on U.S. stock- and bond-market. Safe haven assets have a negative beta during turbulent times and therefore the period of 2020-01-01 to 2022-03-31 will be analyzed. A period of five years leading up to the pandemic as well as the turbulent time period will be used as an average to enable comparison between regular and trying times. The results conclude that neither Bitcoin nor gold can be viewed as safe haven assets. However, it is found that both assets can work as diversifiers in the two markets.
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Volatility Forecasting Performance: Evaluation of GARCH type volatility models on Nordic equity indicesWennström, Amadeus January 2014 (has links)
This thesis examines the volatility forecasting performance of six commonly used forecasting models; the simple moving average, the exponentially weighted moving average, the ARCH model, the GARCH model, the EGARCH model and the GJR-GARCH model. The dataset used in this report are three different Nordic equity indices, OMXS30, OMXC20 and OMXH25. The objective of this paper is to compare the volatility models in terms of the in-sample and out-of-sample fit. The results were very mixed. In terms of the in-sample fit, the result was clear and unequivocally implied that assuming a heavier tailed error distribution than the normal distribution and modeling the conditional mean significantly improves the fit. Moreover a main conclusion is that yes, the more complex models do provide a better in-sample fit than the more parsimonious models. However in terms of the out-of-sample forecasting performance the result was inconclusive. There is not a single volatility model that is preferred based on all the loss functions. An important finding is however not only that the ranking differs when using different loss functions but how dramatically it can differ. This illuminates the importance of choosing an adequate loss function for the intended purpose of the forecast. Moreover it is not necessarily the model with the best in-sample fit that produces the best out-of-sample forecast. Since the out-of-sample forecast performance is so vital to the objective of the analysis one can question whether the in-sample fit should even be used at all to support the choice of a specific volatility model.
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Dynamic Response of a Tied Arch Bridge to a Choice of Loading & Operation Conditions : A case study of the Urmia Lake BridgeMahan, Amir January 2009 (has links)
No description available.
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Entwurf, Konstruktion und Berechnung einer eingleisigen Eisenbahnbrücke als Netzwerkbogenbrücke in StahlbauweiseSchwabe, Daniel 10 July 2019 (has links)
In dieser Arbeit wurde eine 110 m weit spannende Netzwerkbogenbrücke für eingleisigen Eisenbahnverkehr unter Lastmodell (LM) 71, auf Basis der Forschungsergebnisse Teichs entworfen und nach den Vorgaben der DIN EN 1990, 1991 und 1993 bemessen. Im Rahmen des Entwurfs wurde eine Variantenuntersuchung durchgeführt. Ferner wurde ein Montagekonzept erstellt.
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Vagal Afferent Innervation and Remodeling in the Aortic Arch of Young-Adult Fischer 344 Rats Following Chronic Intermittent HypoxiaAi, J., Wurster, R. D., Harden, S. W., Cheng, Z. J. 01 December 2009 (has links)
Previously, we have shown that chronic intermittent hypoxia (CIH) impairs baroreflex control of heart rate and augments aortic baroreceptor afferent function. In the present study, we examined whether CIH induces structural changes of aortic afferent axons and terminals. Young-adult Fischer 344 (F344, 4 months old) rats were exposed to room air (RA) or CIH for 35-45 days. After 14-24 days of exposure, they received tracer DiI injection into the left nodose ganglion to anterogradely label vagal afferent nerves. After surgery, animals were returned to their cages to continue RA or CIH exposure. Twenty-one days after DiI injection, the animals were sacrificed and the aortic arch was examined using confocal microscopy. In both RA and CIH rats, we found that DiI-labeled vagal afferent axons entered the wall of the aortic arch, then fanned out and branched into large receptive fields with numerous terminals (flower-sprays, end-nets and free endings). Vagal afferent axons projected much more to the anterior wall than to the posterior wall. In general, the flower-sprays, end-nets and free endings were widely and similarly distributed in the aortic arch of both groups. However, several salient differences between RA and CIH rats were found. Compared to RA control, CIH rats appeared to have larger vagal afferent receptive fields. The CIH rats had many abnormal flower-sprays, end-nets, and free endings which were intermingled and diffused into "bush-like" structures. However, the total number of flower-sprays was comparable (P>0.05). Since there was a large variance of the size of flower-sprays, we only sampled the 10 largest flower-sprays from each animal. CIH substantially increased the size of large flower-sprays (P<0.01). Numerous free endings with enlarged varicosities were identified, resembling axonal sprouting structures. Taken together, our data indicate that CIH induces significant remodeling of afferent terminal structures in the aortic arch of F344 rats. We suggest that such an enlargement of vagal afferent terminals may contribute to altered aortic baroreceptor function following CIH.
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Impact of cerebral protection strategy used during open surgical aortic arch replacement on visceral functionAl-Sabri, Saddam Mohammed Ahmed 02 June 2020 (has links)
No description available.
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Experiments on the Response of Arch-Supported Membrane Shelters to Snow and Wind LoadingCarradine, David Marc 28 April 1998 (has links)
For many years, inflatable structures and membrane enclosed structures have proved useful for a variety of purposes, such as athletic pavilions, exhibition spaces, coliseums, and kiosks. More recently, structures that combine highly pressurized inflatable arch members with light fabric membrane coverings have been considered for use as a variation of such structural systems. The United States Army has begun to investigate pressurized arch-supported membrane shelters that would be large, lightweight, and easily erected in a short amount of time. These shelters are proposed for a variety of purposes, including aircraft hangars, vehicle maintenance shelters, and medical aid stations.
The specific contribution of this study was the creation and testing of scale models to obtain a better understanding of how these structures behave under wind and snow loading conditions. Three models were constructed, one at a scale of 1:100 and two at a scale of 1:50. The 1:100 scale model represented a proposed prototypical structure 200 ft long, 75 ft wide, and 50 ft tall, with multiple arches. Of the 1:50 scale models, one model represented a structure with the same dimensions as the 1:100 scale model and the other represented a single arch from one of the proposed prototypical structures. Both of the full structural models were wind and snow load tested. The single arch model was tested under full and partial snow loading. Data from the testing were collected, tabulated, and evaluated. The experimental results are discussed, conclusions are drawn, and recommendations for further research are presented. / Master of Science
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Lávka tvořená předpjatým pásem s obloukem / Footbridge formed by a stress ribbon and archGlajcar, Karel January 2012 (has links)
The subject of this master’s thesis is the design of footbridge across the river. The main objective is to analyse the superstructure which is formed by a stress ribbon and arch. The arch consists of two separate plan curved concrete arches and is associated with stress ribbon in the top. The analysis of the structure has been performed using MIDAS CIVIL 2011 software. Simplified calculations by hand or by EXCEL have been also carried out. Design of the superstructure's elements, pre-stressed tendons and reinforcement has been done according to EUROCODE. In the analysis, time dependent effects have been also taken into account.
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Rekonstrukce mostu / Reconstruction of the road bridgeRolenc, Jan January 2012 (has links)
Content of this master's thesis is reconstruction of road brigre and determination of its load capacity before and after reconstruction.
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Vodojemy - Brno, Žlutý kopec / Reservoirs - Brno, Zluty kopec (Yellow hill)Tomanová, Tereza Unknown Date (has links)
The diploma thesis deals with the possible use of now defunct reservoirs on the Yellow Hill. This water supply complex consists of three underground reservoirs and a technical house. The area is spread over a large plot of land overgrown with wild vegetation in the middle of a residential area. The set of underground reservoirs, covered by a system of arches supported by pillars, represents a unique architectural and technical monument. The aim of the proposal is to make the reservoir area accessible to the public through new functions while preserving their historical value. The main motive of the concept is an interactive water museum built in the youngest reinforced concrete reservoir. The exhibition deals, among other things, with a very current topic of sustainable water management. The complex is complemented by a new visitor center, which will make it possible to access the reservoirs through a new entrance to the underground. The existing unmaintained area of greenery will be transformed into a public park independent of the operation of reservoirs.
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