Transient modeling of the thermohydraulic behavior of high temperature heat pipes for space reactor applications

Many proposed space reactor designs employ heat pipes as a means of conveying heat. Previous researchers have been concerned with steady state operation, but the transient operation is of interest in space reactor applications due to the necessity of remote startup and shutdown. A model is being developed to study the dynamic behavior of high temperature heat pipes during startup, shutdown and normal operation under space environments. Model development and preliminary results for a hypothetical design of the system are presented

Tethers

A tether of sufficient strength, capable of being lengthened or shortened and having appropriate apparatuses for capturing and releasing bodies at its ends, may be useful in propulsion applications. For example, a tether could allow rendezvous between spacecraft in substantially different orbits without using propellant. A tether could also allow co-orbiting spacecraft to exchange momentum and separate. Thus, a reentering spacecraft (such as the Shuttle) could give its momentum to one remaining on orbit (such as the space station). Similarly, a tether facility could gain momentum from a high I(sub sp)/low thrust mechanism (which could be an electrodynamics tether) and transfer than momentum by means of a tether to payloads headed for many different orbits. Such a facility would, in effect, combine high I(sub sp) with high thrust, although only briefly. An electrodynamic tether could propel a satellite from its launch inclination to a higher or lower inclination. Tethers could also allow samples to be taken from bodies such as the Moon. Three types of tether operations are illustrated. The following topics are discussed: (1) tether characteristics; (2) tether propulsion methods--basics, via momentum transfer, and electrodynamic tether propulsion; and (3) their use in planetary exploration

Development of a linearized unsteady aerodynamic analysis for cascade gust response predictions

A method for predicting the unsteady aerodynamic response of a cascade of airfoils to entropic, vortical, and acoustic gust excitations is being developed. Here, the unsteady flow is regarded as a small perturbation of a nonuniform isentropic and irrotational steady background flow. A splitting technique is used to decompose the linearized unsteady velocity into rotational and irrotational parts leading to equations for the complex amplitudes of the linearized unsteady entropy, rotational velocity, and velocity potential that are coupled only sequentially. The entropic and rotational velocity fluctuations are described by transport equations for which closed-form solutions in terms of the mean-flow drift and stream functions can be determined. The potential fluctuation is described by an inhomogeneous convected wave equation in which the source term depends on the rotational velocity field, and is determined using finite-difference procedures. The analytical and numerical techniques used to determine the linearized unsteady flow are outlined. Results are presented to indicate the status of the solution procedure and to demonstrate the impact of blade geometry and mean blade loading on the aerodynamic response of cascades to vortical gust excitations. The analysis described herein leads to very efficient predictions of cascade unsteady aerodynamic response phenomena making it useful for turbomachinery aeroelastic and aeroacoustic design applications

Post-Election Audits: Restoring Trust in Elections

With the intention of assisting legislators, election officials and the public to make sense of recent literature on post-election audits and convert it into realistic audit practices, the Brennan Center and the Samuelson Law, Technology and Public Policy Clinic at Boalt Hall School of Law (University of California Berkeley) convened a blue ribbon panel (the "Audit Panel") of statisticians, voting experts, computer scientists and several of the nation's leading election officials. Following a review of the literature and extensive consultation with the Audit Panel, the Brennan Center and the Samuelson Clinic make several practical recommendations for improving post-election audits, regardless of the audit method that a jurisdiction ultimately decides to adopt

Was the “S” for Silent?: The Maine Indian Land Claims and Senator Edmund S. Muskie

This article explores the work of one of Maine’s most powerful politicians, U.S. Senator Edmund Muskie, during one of Maine’s most difficult political crises, the Maine Indian Land Claims of the 1970s. In 1972, when Penobscots and Passamaquoddies challenged the legality of land sales conducted from 1794 to 1833, they called into question the legal title of the northern two-thirds of the State of Maine. Tom Tureen, the lawyer for the tribes, and Governor James Longley and State Attorney General Joseph Brennan, the state officials leading the case for Maine, played central roles in the case. Muskie played a crucial, if less important, role by advocating for a negotiated settlement that prevented a protracted legal fight. Muskie’s more limited involvement was rooted, in part, in his preference to be a negotiator rather than an advocate in this particular case, but it also was a product of his lack of experience with Maine Indian issues. Muskie’s restraint had important consequences for the case, because it allowed more vocally anti-Indian state leaders like Longley and Brennan to shape the rhetoric that would define the controversy long after the case was settled in 1980. Joseph Hall is an Associate Professor of History at Bates College, where he teaches and studies Native American history and early American history

Charitable Practices of Muslim Americans in the Greater Kansas City Area

The purpose of this research is to explore the state of post-9/11 Muslim American philanthropy within The Greater Kansas City Area. Since 2001, the U.S. government has expanded its counterterrorism policies to target sources of terrorist funding and in particular the charitable sector. Many Muslim Americans practice the Islamic traditions of zakât (obligatory alms) and ṣadaqah (discretionary charity) as a means of honoring faith, strengthening the community and preserving religious identity. There is a perception, however, that these practices are in direct conflict with U.S. counterterrorism policy. The outcome of the decade long War on Terrorism is telling; to date, The U.S. Treasury's Office of Foreign Assets Control (OFAC) has shut down seven US-based Islamic charities and frozen over $2.3 billion in charitable assets (TAR, 2012: 2) in the effort to stem terrorist funding. These actions were taken under the auspices of national security, however, they gave a perception that U.S. policies trump Muslim American civil rights and discourage Islamic philanthropy; "The passage of both USA Patriot Acts, the closing of several Muslim charities, and the curbing of civil liberties beginning with the Bush administration and continuing through the Obama administration have caused contributions to Muslim American charities, especially those with an international scope, to decrease by up to 50 percent in the initial years." (Jamal, 2011: 5). The Greater Kansas City Area is no stranger to Islamic culture; according to The Association of Religion Data Archives (ARDA), it has the 98th largest Muslim population out of 133 U.S. metropolitan centers with eighteen active Islamic congregations (thearda.com). The significant Kansas City Muslim population coupled with a recent stigmatization of Islam drives this primary research question: How have post-9/11 U.S. policies impacted Islamic charitable practices of Muslim Americans in the Greater Kansas City Area. This study employs a mixed-method research approach to answering this thesis question. First, it examines 30 years of U.S. policies that culminates in the `securitization' of the nonprofit sector. This research then conducts a comparative analysis of annual budgets from six Muslim and six non-Muslim charities in Kansas City to identify donation patterns since 9/11. Lastly, this study analyzes the results of focus group discussions conducted with fourteen volunteers from the Islamic Center of Johnson County (ICJC), Kansas City, Kansas to identify changes in individual charity over the last 10 years. The results of this research suggest that Kansas City's Islamic charities benefited from Muslim philanthropy in spite of post-9/11 U.S. counterterrorism policies. Additionally this research suggests that Muslim Americans in Kansas City continue to practice innovative forms of charity regardless of prevailing concerns of civil-rights infringement. This research on the Kansas City Muslim American minority complements an academic narrative derived from research in other major U.S. metropolitan centers (Najam, Abraham, Howell, Shryock, and Hadaad). Its findings can be used to inform the opinions of local community leaders and serve as a starting point for broader, more comprehensive research on Kansas City's Muslim community

Schurly you're joking - quantum-classical correspondence in phase space for non-Hermitian systems

In closed quantum systems described by Hermitian Hamiltonians the Husimi distributions of stationary states are closely related to classical phase space structures. To each state there is assigned a unique area of the Planck cell partitioned phase space. The localisation of the stationary states upon specific regions of phase space can be related to the classical dynamics and energies. In systems described by non-normal operators, and in particular non-Hermitian Hamiltonians, the general non-orthogonality of the stationary states stands in the way of the application of many standard ideas of quantum-classical correspondence. Many of these can be recovered if the Schur vectors are used instead of the eigenvectors. For specific classes of non-Hermitian systems, with simple loss profiles, this correspondence between the Schur vectors and features of the classical phase space are well investigated. For general non-Hermitian systems with more complex gain-loss profiles, however, there is a lack of methods and understanding. In this thesis we will address this problem by associating to each Schur vector an area of phase space described by the classical analogue of the quantum norm, which we describe as classical norm maps. An algorithm will be introduced that constructs from the norm maps a classical density that shows remarkably close correspondence to the Husimi distributions of the Schur vectors. We will demonstrate this correspondence in both regular and chaotic non-Hermitian systems.Open Acces

Minimisation of energy consumption variance for multi-process manufacturing lines through genetic algorithm manipulation of production schedule

Typical manufacturing scheduling algorithms do not consider the energy consumption of each job, or its variance, when they generate a production schedule. This can become problematic for manufacturers when local infrastructure has limited energy distribution capabilities. In this paper, a genetic algorithm based schedule modification algorithm is presented. By referencing energy consumption models for each job, adjustments are made to the original schedule so that it produces a minimal variance in the total energy consumption in a multi-process manufacturing production line, all while operating within the constraints of the manufacturing line and individual processes. Empirical results show a significant reduction in energy consumption variance can be achieved on schedules containing multiple concurrent jobs

Ultrafast switching of photonic entanglement

To deploy and operate a quantum network which utilizes existing telecommunications infrastructure, it is necessary to be able to route entangled photons at high speeds, with minimal loss and signal-band noise, and---most importantly---without disturbing the photons' quantum state. Here we present a switch which fulfills these requirements and characterize its performance at the single photon level; it exhibits a 200-ps switching window, a 120:1 contrast ratio, 1.5 dB loss, and induces no measurable degradation in the switched photons' entangled-state fidelity (< 0.002). Furthermore, because this type of switch couples the temporal and spatial degrees of freedom, it provides an important new tool with which to encode multiple-qubit states in a single photon. As a proof-of-principle demonstration of this capability, we demultiplex a single quantum channel from a dual-channel, time-division-multiplexed entangled photon stream, effectively performing a controlled-bit-flip on a two-qubit subspace of a five-qubit, two-photon state

Pacifying Paradise: Violence and Vigilantism in San Luis Obispo

San Luis Obispo, California was a violent place in the 1850s with numerous murders and lynchings in staggering proportions. This thesis studies the rise of violence in SLO, its causation, and effects. The vigilance committee of 1858 represents the culmination of the violence that came from sweeping changes in the region, stemming from its earliest conquest by the Spanish. The mounting violence built upon itself as extensive changes took place. These changes include the conquest of California, from the Spanish mission period, Mexican and Alvarado revolutions, Mexican-American War, and the Gold Rush. The history of the county is explored until 1863 to garner an understanding of the borderlands violence therein