Epstein-Zin Utility Maximization on a Random Horizon

This paper solves the consumption-investment problem under Epstein-Zin preferences on a random horizon. In an incomplete market, we take the random horizon to be a stopping time adapted to the market filtration, generated by all observable, but not necessarily tradable, state processes. Contrary to prior studies, we do not impose any fixed upper bound for the random horizon, allowing for truly unbounded ones. Focusing on the empirically relevant case where the risk aversion and the elasticity of intertemporal substitution are both larger than one, we characterize the optimal consumption and investment strategies using backward stochastic differential equations with superlinear growth on unbounded random horizons. This characterization, compared with the classical fixed-horizon result, involves an additional stochastic process that serves to capture the randomness of the horizon. As demonstrated in two concrete examples, changing from a fixed horizon to a random one drastically alters the optimal strategies

The Origins of Mesoamerican Civilization

This research project will attempt to unravel the various threads of cultural influence that existed in Archaic Mesoamerica. Of particular interest will be to test the validity of the theory that there is a “mother culture,” usually posited as the Olmec, which was responsible for the innovations that led to the social complexities of later cultures such as the Mayans and Aztecs. Alternately, it is possible that innovations developed by several different cultures were shared through diffusion due to strong trade networks and other methods. This research question is important because it deals with the evolutionary development of advanced social structures and complex societies. Historical data will be examined to see if there is any bias towards one of these competing viewpoints. Of particular interest will be to look for parallels between the development of these civilizations and ones that developed around the same time in the Middle East and Asia. Finally, several archaeological case studies will be examined to attempt to fit the evidence within one of these theoretical frameworks and show how archaeological evidence can facilitate theory formation.https://scholarscompass.vcu.edu/uresposters/1073/thumbnail.jp

Reverberation Chamber Immunity Testing : A novel methodology to avoid accidental DUT damage

Abstract—This paper shows a novel method of measuring the immunity of electronic devices inside reverberation chambers. Rather than using mode stirring or mode tuning with a constant power input into the chamber, we will present a method based on variable power that protects the DUT against accidental damage and also gives more information about the hardness of the DUT than the traditional methods

The Patient Protection And Affordable Care Act And Medicaid Expansion: Leadership Strategies For Effective Change Management In Managed Care Organizations

As a result of tlie 2010 Patient Protection and Affordable Care Act (ACA), eligibility requirements for the Medicaid program were revised resulting in a greater number of people eligible to enroll in tlie government healthcare program. These circumstances require numerous organizational changes for Medicaid managed care organizations (MCOs) that administer the Medicaid program in order to accommodate the healthcare needs of the growing Medicaid population and comply with applicable regulatory requirements. This case study sought to identify effective leadership strategies employed by Minnesota Medicaid MCO change leaders guiding organizational change processes and seeking quality change outcomes, resulting from the externally imposed change. Minnesota Medicaid MCOs were chosen for this study as Minnesota accepted the option to expand the Medicaid eligibility requirements prior to the national mandate in 2014, creating opportunity to learn from those leadership experiences and share the information with leaders who will face similar changes in the future. This exploratory research identified three components to support successful change leadership in this context, including collaboration, planning and preparing, and communication. This research contributes to a void in existing literature on change leadership and change management, which has historically focused on internal change initiatives

Avalanche of stimulated forward scattering in high harmonic generation

© 2016 [Optical Society of America]. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited.Optical amplifiers in all ranges of the electromagnetic spectrum exhibit an essential characteristic, namely the input signal during the propagation in the amplifier medium is multiplied by the avalanche effect of the stimulated emission to produce exponential growth. We perform a theoretical study motivated and supported by experimental data on a He gas amplifier driven by intense 30-fs-long laser pulses and seeded with attosecond pulse trains generated in a separated Ne gas jet. We demonstrate that the strong-field theory in the frame of high harmonic generation fully supports the appearance of the avalanche effect in the amplification of extreme ultraviolet attosecond pulse trains. We theoretically separate and identify different physical processes taking part in the interaction and we demonstrate that X-ray parametric amplification dominates over others. In particular, we identify strong-field mediated intrapulse X-ray parametric processes as decisive for amplification at the single-atom level. We confirm that the amplification takes place at photon energies where the amplifier is seeded and when the seed pulses are perfectly synchronized with the driving strong field in the amplifier. Furthermore, propagation effects, phase matching and seed synchronization can be exploited to tune the amplified spectral range within the seed bandwidth.Peer ReviewedPostprint (author's final draft