Computation methods for the eigenvalue analysis of large structures by component synthesis

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A “Human Endeavor”: Killing In Contemporary U.S. Combat Narratives

This PH.D dissertation aims to develop a 3-D numerical model of dam-break flows on movable beds. Three tasks are defined to accomplish the goal of this study. The first task is developing a 3-D hydrodynamic model to simulate dam-break flow on fixed beds with simple geometry and test the water surface tracking technique. This model solves the Reynolds-averaged Navier-Stokes (RANS) equations using a finite-difference method on rectilinear, staggered grids. The volume-of-fluid (VOF) technique with SOLA-VOF advection scheme is used to capture the free surface motion. The developed model is tested using several experimental dam-break flows and the VOF technique is found to be able to effectively treat the rapidly-varying water surface boundary of dam-break flows. As the second task of this dissertation, a 3-D finite-volume model is developed to simulate dam-break flows on irregular fixed beds. Developing this model is necessary to accomplish the major goal of this dissertation since the finite-difference model explained above, which uses the rectilinear staggered grid, is not convenient to extend to the case of irregular and movable beds and integrate with sediment transport calculations. This model solves the RANS equations using a finite-volume method on irregular hexahedral, collocated meshes and adopts the compressive interface capturing scheme for arbitrary meshes (CICSAM) as the VOF advection method. The model is tested by means of experimental dam-break flows on fixed beds with simple and irregular geometries. The final task is extending the 3-D finite-volume model to a dam-break flow model applicable on movable beds. Therefore, it is integrated with a sediment transport model developed in this study. The sediment transport model solves the non-equilibrium transport equations of suspended load and bed load separately and in turn calculates the resulting bed change, based on the flow properties calculated by the hydrodynamic model. Since the time evolution of bed topography affects the hydrodynamic calculations, the model uses a moving grid technique to update the computational grid to fit on the calculated bed topography at every time step. The grid moving velocity and the computational cell volume change generated by the moving mesh are taken into consideration when the governing equations of the hydrodynamic and sediment transport models are discretized. The integrated model is tested using several experimental dam-break flows on movable beds. The calculated spatial and temporal variations of water and bed surfaces are generally in good agreement with the measured data

Australian fauna and medical science

Professor WM. Colin Mackenzie, M.D., F.R.C.S., F.R.S.-Director National Museum of Australian Zoology. Up till recent times the appeal for the preservation of the unique fauna of our country has been based largely on sentiment. Today, thanks to poison and the gun, we recognise that many of our animals that were common twenty years ago are becoming increasingly rare, and within a short period of time will have completely disappeared, never to be recalled. In this paper I wish to draw attention to what is now the most urgent plea for the preservation of our fauna, viz., its importance for a correct understanding of the human body in health and disease. The animals of Australia and Tasmania are teeming with points of scientific interest. Through them human complexities are revealed in their simpler form. In Canberra, The Research Reservation, is located on Acton Hill, not far from Civic Place, and facing Parliament House and the Capitol site.It is a peninsula of, about 80 acres, bounded by the River Molonglo, and facing Black Mountain. It lies in what is known as the Continental Arboretum. Here will be kept live specimens of Australian and Tasmanian native animals in their natural state. When the buildings are erected Canberra will become the world's centre for the study of our unique fauna and every facility will be offered to workers not only Australian, but also from abroad, wishing to study comparative anatomy and its application to modern medical and surgical practice

Prices versus Quantities versus Bankable Quantities

Quantity-based regulation with banking allows regulated firms to shift obligations across time in response to periods of unexpectedly high or low marginal costs. Despite its wide prevalence in existing and proposed emission trading programs, banking has received limited attention in past welfare analyses of policy choice under uncertainty. We address this gap with a model of banking behavior that captures two key constraints: uncertainty about the future from the firm’s perspective and a limit on negative bank values (e.g., borrowing). We show conditions where banking provisions reduce price volatility and lower expected costs compared to quantity policies without banking. For plausible parameter values related to U.S. climate change policy, we find that bankable quantities produce behavior quite similar to price policies for about two decades and, during this period, improve welfare by about a $1 billion per year over fixed quantities.

Prices versus Quantities versus Bankable Quantities

Welfare comparisons of regulatory instruments under uncertainty, even in dynamic analyses, have typically focused on price versus quantity controls despite the presence of banking and borrowing provisions in existing emissions trading programs. This is true even in the presence of banking and borrowing provisions in existing emissions trading programs. Nonetheless, many have argued that such provisions can reduce price volatility and lower costs in the face of uncertainty, despite any theoretical or empirical evidence. This paper develops a model and solves for optimal banking and borrowing behavior with uncertain cost shocks that are serially correlated. We show that while banking does reduce price volatility and lowers costs, the degree of these reductions depends on the persistence of shocks. For plausible parameter values related to U.S. climate change policy, we find that bankable quantities eliminate about 20 percent of the cost difference between price and nonbankable quantities.welfare, prices, quantities, climate change

A Thermal RC Model Including Thermal Mass and Solar Gain Effects for Building Energy Simulation

Building Commissioning is important for evaluating energy and dollar savings in existing buildings. Energy Systems Lab of Texas A&M University has developed WinAM with the purpose of aiding that process. WinAM is a steady-state calculation engine tool that computes energy and dollar savings for commissioning purposes in existing buildings. However, the problem can rise with WinAM’s simplified calculation method rendering inaccurate results. This research proposes a Resistance-Capacitance (RC) model be added to the current WinAM model that incorporates the effects of solar heat gains and thermal mass effects. The RC model is tested against 11 simulation cases with EnergyPlus™, a building energy simulation program, and the current WinAM version. Parameters are changed in all models to analyze the proposed RC model against EnergyPlus results. The results show that the RC model achieves better performance than WinAM when compared to EnergyPlus. The extreme case differs of 286% for annual heating consumption between the RC model and EnergyPlus, while WinAM differs in 4040% for annual heating consumption when compared to EnergyPlus. The RC model annual heating and cooling consumption results approximates better to EnergyPlus in more than 90% of the cases analyzed. Energy savings are estimated for the cases of temperature setback and dead-band temperature set points, for seven different weather conditions and three different building masses. A case study is also analyzed of a real building, each model is calibrated to the building’s metered energy consumption, and applied energy efficiency measures (EEMs) to the models, comparing each model’s estimated savings. For the case study, the estimated savings from all models when temperature set back and temperature dead-band are applied present similar estimated savings. The extreme cases are of WinAM over predicting savings for temperature set back such as 47% for annual heating consumption, while RC predicts 27% and EnergyPlus only predicts 6%, and WinAM under predicting savings for temperature dead-band such as 31% for annual heating consumption, while RC predicts 96%, and EnergyPlus predicts 99% savings. The RC model presents improvement from the current WinAM model in 53/55 of simulated cases of the estimated savings when compared to EnergyPlus estimated savings