6 resultados para Metal in the architecture
em Digital Commons - Michigan Tech
Resumo:
Life-Patterns on the Periphery: A Humanities Base for Development Imperatives and their Application in the Chicago City-Region is informed by the need to bring diverse fields together in order to tackle issues related to the contemporary city-region. By honouring the long-term economic, social, political, and ecological imperatives that form the fabric of healthy, productive, sustainable communities, it becomes possible to setup political structures and citizen will to develop distinct places that result in the overlapping of citizen life patterns, setting the stage for citizen action and interaction. Based in humanities scholarship, the four imperatives act as checks on each other so that no one imperative is solely honoured in development. Informed by Heidegger, Arendt, deCerteau, Casey, and others, their foundation in the humanities underlines their importance, while at the same time creating a stage where all fields can contribute to actualizing this balance in practice. For this project, theoretical assistance has been greatly borrowed from architecture, planning theory, urban theory, and landscape urbanism, including scholarship from Saskia Sassen, John Friedmann, William Cronon, Jane Jacobs, Joel Garreau, Alan Berger, and many others. This project uses the Chicago city-region as a site, specifically the Interstate 80 and 88 corridors extending west from Chicago. Both transportation corridors are divided into study regions, providing the opportunity to examine a broad variety of population and development densities. Through observational research, a picture of each study region can be extrapolated, analyzed, and understood with respect to the four imperatives. This is put to use in this project by studying region-specific suggestions for future development moves, culminating in some universal steps that can be taken to develop stronger communities and set both the research site specifically and North American city-regions in general on a path towards healthy, productive, sustainable development.
Resumo:
The time course of lake recovery after a reduction in external loading of nutrients is often controlled by conditions in the sediment. Remediation of eutrophication is hindered by the presence of legacy organic carbon deposits, that exert a demand on the terminal electron acceptors of the lake and contribute to problems such as internal nutrient recycling, absence of sediment macrofauna, and flux of toxic metal species into the water column. Being able to quantify the timing of a lake’s response requires determination of the magnitude and lability, i.e., the susceptibility to biodegradation, of the organic carbon within the legacy deposit. This characterization is problematic for organic carbon in sediments because of the presence of different fractions of carbon, which vary from highly labile to refractory. The lability of carbon under varied conditions was tested with a bioassay approach. It was found that the majority of the organic material found in the sediments is conditionally-labile, where mineralization potential is dependent on prevailing conditions. High labilities were noted under oxygenated conditions and a favorable temperature of 30 °C. Lability decreased when oxygen was removed, and was further reduced when the temperature was dropped to the hypolimnetic average of 8° C . These results indicate that reversible preservation mechanisms exist in the sediment, and are able to protect otherwise labile material from being mineralized under in situ conditions. The concept of an active sediment layer, a region in the sediments in which diagenetic reactions occur (with nothing occurring below it), was examined through three lines of evidence. Initially, porewater profiles of oxygen, nitrate, sulfate/total sulfide, ETSA (Electron Transport System Activity- the activity of oxygen, nitrate, iron/manganese, and sulfate), and methane were considered. It was found through examination of the porewater profiles that the edge of diagenesis occurred around 15-20 cm. Secondly, historical and contemporary TOC profiles were compared to find the point at which the profiles were coincident, indicating the depth at which no change has occurred over the (13 year) interval between core collections. This analysis suggested that no diagenesis has occurred in Onondaga Lake sediment below a depth of 15 cm. Finally, the time to 99% mineralization, the t99, was viewed by using a literature estimate of the kinetic rate constant for diagenesis. A t99 of 34 years, or approximately 30 cm of sediment depth, resulted for the slowly decaying carbon fraction. Based on these three lines of evidence , an active sediment layer of 15-20 cm is proposed for Onondaga Lake, corresponding to a time since deposition of 15-20 years. While a large legacy deposit of conditionally-labile organic material remains in the sediments of Onondaga Lake, it becomes clear that preservation, mechanisms that act to shield labile organic carbon from being degraded, protects this material from being mineralized and exerting a demand on the terminal electron acceptors of the lake. This has major implications for management of the lake, as it defines the time course of lake recovery following a reduction in nutrient loading.
Resumo:
Metals price risk management is a key issue related to financial risk in metal markets because of uncertainty of commodity price fluctuation, exchange rate, interest rate changes and huge price risk either to metals’ producers or consumers. Thus, it has been taken into account by all participants in metal markets including metals’ producers, consumers, merchants, banks, investment funds, speculators, traders and so on. Managing price risk provides stable income for both metals’ producers and consumers, so it increases the chance that a firm will invest in attractive projects. The purpose of this research is to evaluate risk management strategies in the copper market. The main tools and strategies of price risk management are hedging and other derivatives such as futures contracts, swaps and options contracts. Hedging is a transaction designed to reduce or eliminate price risk. Derivatives are financial instruments, whose returns are derived from other financial instruments and they are commonly used for managing financial risks. Although derivatives have been around in some form for centuries, their growth has accelerated rapidly during the last 20 years. Nowadays, they are widely used by financial institutions, corporations, professional investors, and individuals. This project is focused on the over-the-counter (OTC) market and its products such as exotic options, particularly Asian options. The first part of the project is a description of basic derivatives and risk management strategies. In addition, this part discusses basic concepts of spot and futures (forward) markets, benefits and costs of risk management and risks and rewards of positions in the derivative markets. The second part considers valuations of commodity derivatives. In this part, the options pricing model DerivaGem is applied to Asian call and put options on London Metal Exchange (LME) copper because it is important to understand how Asian options are valued and to compare theoretical values of the options with their market observed values. Predicting future trends of copper prices is important and would be essential to manage market price risk successfully. Therefore, the third part is a discussion about econometric commodity models. Based on this literature review, the fourth part of the project reports the construction and testing of an econometric model designed to forecast the monthly average price of copper on the LME. More specifically, this part aims at showing how LME copper prices can be explained by means of a simultaneous equation structural model (two-stage least squares regression) connecting supply and demand variables. A simultaneous econometric model for the copper industry is built: {█(Q_t^D=e^((-5.0485))∙P_((t-1))^((-0.1868) )∙〖GDP〗_t^((1.7151) )∙e^((0.0158)∙〖IP〗_t ) @Q_t^S=e^((-3.0785))∙P_((t-1))^((0.5960))∙T_t^((0.1408))∙P_(OIL(t))^((-0.1559))∙〖USDI〗_t^((1.2432))∙〖LIBOR〗_((t-6))^((-0.0561))@Q_t^D=Q_t^S )┤ P_((t-1))^CU=e^((-2.5165))∙〖GDP〗_t^((2.1910))∙e^((0.0202)∙〖IP〗_t )∙T_t^((-0.1799))∙P_(OIL(t))^((0.1991))∙〖USDI〗_t^((-1.5881))∙〖LIBOR〗_((t-6))^((0.0717) Where, Q_t^D and Q_t^Sare world demand for and supply of copper at time t respectively. P(t-1) is the lagged price of copper, which is the focus of the analysis in this part. GDPt is world gross domestic product at time t, which represents aggregate economic activity. In addition, industrial production should be considered here, so the global industrial production growth that is noted as IPt is included in the model. Tt is the time variable, which is a useful proxy for technological change. A proxy variable for the cost of energy in producing copper is the price of oil at time t, which is noted as POIL(t ) . USDIt is the U.S. dollar index variable at time t, which is an important variable for explaining the copper supply and copper prices. At last, LIBOR(t-6) is the 6-month lagged 1-year London Inter bank offering rate of interest. Although, the model can be applicable for different base metals' industries, the omitted exogenous variables such as the price of substitute or a combined variable related to the price of substitutes have not been considered in this study. Based on this econometric model and using a Monte-Carlo simulation analysis, the probabilities that the monthly average copper prices in 2006 and 2007 will be greater than specific strike price of an option are defined. The final part evaluates risk management strategies including options strategies, metal swaps and simple options in relation to the simulation results. The basic options strategies such as bull spreads, bear spreads and butterfly spreads, which are created by using both call and put options in 2006 and 2007 are evaluated. Consequently, each risk management strategy in 2006 and 2007 is analyzed based on the day of data and the price prediction model. As a result, applications stemming from this project include valuing Asian options, developing a copper price prediction model, forecasting and planning, and decision making for price risk management in the copper market.
Resumo:
Small clusters of gallium oxide, technologically important high temperature ceramic, together with interaction of nucleic acid bases with graphene and small-diameter carbon nanotube are focus of first principles calculations in this work. A high performance parallel computing platform is also developed to perform these calculations at Michigan Tech. First principles calculations are based on density functional theory employing either local density or gradient-corrected approximation together with plane wave and gaussian basis sets. The bulk Ga2O3 is known to be a very good candidate for fabricating electronic devices that operate at high temperatures. To explore the properties of Ga2O3 at nonoscale, we have performed a systematic theoretical study on the small polyatomic gallium oxide clusters. The calculated results find that all lowest energy isomers of GamOn clusters are dominated by the Ga-O bonds over the metal-metal or the oxygen-oxygen bonds. Analysis of atomic charges suggest the clusters to be highly ionic similar to the case of bulk Ga2O3. In the study of sequential oxidation of these slusters starting from Ga2O, it is found that the most stable isomers display up to four different backbones of constituent atoms. Furthermore, the predicted configuration of the ground state of Ga2O is recently confirmed by the experimental result of Neumark's group. Guided by the results of calculations the study of gallium oxide clusters, performance related challenge of computational simulations, of producing high performance computers/platforms, has been addressed. Several engineering aspects were thoroughly studied during the design, development and implementation of the high performance parallel computing platform, rama, at Michigan Tech. In an attempt to stay true to the principles of Beowulf revolutioni, the rama cluster was extensively customized to make it easy to understand, and use - for administrators as well as end-users. Following the results of benchmark calculations and to keep up with the complexity of systems under study, rama has been expanded to a total of sixty four processors. Interest in the non-covalent intereaction of DNA with carbon nanotubes has steadily increased during past several years. This hybrid system, at the junction of the biological regime and the nanomaterials world, possesses features which make it very attractive for a wide range of applicatioins. Using the in-house computational power available, we have studied details of the interaction between nucleic acid bases with graphene sheet as well as high-curvature small-diameter carbon nanotube. The calculated trend in the binding energies strongly suggests that the polarizability of the base molecules determines the interaction strength of the nucleic acid bases with graphene. When comparing the results obtained here for physisorption on the small diameter nanotube considered with those from the study on graphene, it is observed that the interaction strength of nucleic acid bases is smaller for the tube. Thus, these results show that the effect of introducing curvature is to reduce the binding energy. The binding energies for the two extreme cases of negligible curvature (i.e. flat graphene sheet) and of very high curvature (i.e. small diameter nanotube) may be considered as upper and lower bounds. This finding represents an important step towards a better understanding of experimentally observed sequence-dependent interaction of DNA with Carbon nanotubes.
Resumo:
The development of embedded control systems for a Hybrid Electric Vehicle (HEV) is a challenging task due to the multidisciplinary nature of HEV powertrain and its complex structures. Hardware-In-the-Loop (HIL) simulation provides an open and convenient environment for the modeling, prototyping, testing and analyzing HEV control systems. This thesis focuses on the development of such a HIL system for the hybrid electric vehicle study. The hardware architecture of the HIL system, including dSPACE eDrive HIL simulator, MicroAutoBox II and MotoTron Engine Control Module (ECM), is introduced. Software used in the system includes dSPACE Real-Time Interface (RTI) blockset, Automotive Simulation Models (ASM), Matlab/Simulink/Stateflow, Real-time Workshop, ControlDesk Next Generation, ModelDesk and MotoHawk/MotoTune. A case study of the development of control systems for a single shaft parallel hybrid electric vehicle is presented to summarize the functionality of this HIL system.
Resumo:
The Koyukuk Mining District was one of several northern, turn of the century, gold rush regions. Miners focused their efforts in this region on the Middle Fork of the Koyukuk River and on several of its tributaries. Mining in the Koyukuk began in the 1880s and the first rush occurred in 1898. Continued mining throughout the early decades of the 1900s has resulted in an historic mining landscape consisting of structures, equipment, mining shafts, waste rock, trash scatters, and prospect pits. Modern work continues in the region alongside these historic resources. An archaeological survey was completed in 2012 as part of an Abandoned Mine Lands survey undergone with the Bureau of Land Management, Michigan Technological University, and the University of Alaska Anchorage. This thesis examines the discrepancy between the size of mining operations and their respective successes in the region while also providing an historical background on the region and reports on the historical resources present.