Figure of merit for direct-detection optical channels

The capacity and sensitivity of a direct-detection optical channel are calculated and compared to those of a white Gaussian noise channel. Unlike Gaussian channels in which the receiver performance can be characterized using the noise temperature, the performance of the direct-detection channel depends on both signal and background noise, as well as the ratio of peak to average signal power. Because of the signal-power dependence of the optical channel, actual performance of the channel can be evaluated only by considering both transmit and receive ends of the systems. Given the background noise power and the modulation bandwidth, however, the theoretically optimum receiver sensitivity can be calculated. This optimum receiver sensitivity can be used to define the equivalent receiver noise temperature and calculate the corresponding G/T product. It should be pointed out, however, that the receiver sensitivity is a function of signal power, and care must be taken to avoid deriving erroneous projections of the direct-detection channel performance

Study of the Wealth Inequality in the Minority Game

To demonstrate the usefulness of physical approaches for the study of realistic economic systems, we investigate the inequality of players' wealth in one of the most extensively studied econophysical models, namely, the minority game (MG). We gauge the wealth inequality of players in the MG by a well-known measure in economics known as the modified Gini index. From our numerical results, we conclude that the wealth inequality in the MG is very severe near the point of maximum cooperation among players, where the diversity of the strategy space is approximately equal to the number of strategies at play. In other words, the optimal cooperation between players comes hand in hand with severe wealth inequality. We also show that our numerical results in the asymmetric phase of the MG can be reproduced semi-analytically using a replica method.Comment: 9 pages in revtex 4 style with 3 figures; minor revision with a change of title; to appear in PR

Rotten Bananas, Hip Hop Heads, and the American Individual: Teaching Eddie Huang’s Memoir Fresh Off the Boat and Its Tropes of Literacy

This essay focuses on Fresh Off the Boat as an eminently teachable coming-of-age story, provides critical contexts and directions for teaching this ideologically suggestive text, and sets forth the interpretive argument that the structures and themes of the memoir are fundamentally shaped by the literacy narrative at its core. As such, the text enters into conversation with other literacy narratives that have become so foundational in the teaching of multiethnic literature in the U.S. Moreover, Huang’s tropes of literacy draw from enduring, mythified Americanist discourses that are suggestive of a masculine individualism that, while not unique, is recognizable, instructive, and even problematic as an illustration of a powerful discourse of self-formation. In an effort to speak not only to specialists in U.S. multiethnic literature but also to nonspecialists/generalists, this discussion offers a tripartite approach to teaching this memoir: opening the unit with a sustained, critical, and creative discussion of genre(s), including traditional and popular forms; then inviting students to hone their critical thinking skills through careful rhetorical and ideological analyses of the text’s representations of race, identity, assimilation, and resistance; and ultimately setting forth a focused, conceptual argument about Fresh Off the Boat as a “literacy narrative” while placing the text within a broader U.S. literary history and discourse about the American individual

Structural analysis of viscoelastic materials under thermal and pressure loading

Technique computes stresses resulting from axisymmetric transient thermal loading in circular solid-propellant grain section with circular ports. Propellant is assumed to be linear, thermal rheologically simple, viscoelastic material; material properties are represented by exponential series in time