Radiation environment and shielding for early manned Mars missions

The problem of shielding a crew during early manned Mars missions is discussed. Requirements for shielding are presented in the context of current astronaut exposure limits, natural ionizing radiation sources, and shielding inherent in a particular Mars vehicle configuration. An estimated range for shielding weight is presented based on the worst solar flare dose, mission duration, and inherent vehicle shielding

Performance of a spin-based insulated gate field effect transistor

Fundamental physical properties limiting the performance of spin field effect transistors are compared to those of ordinary (charge-based) field effect transistors. Instead of raising and lowering a barrier to current flow these spin transistors use static spin-selective barriers and gate control of spin relaxation. The different origins of transistor action lead to distinct size dependences of the power dissipation in these transistors and permit sufficiently small spin-based transistors to surpass the performance of charge-based transistors at room temperature or above. This includes lower threshold voltages, smaller gate capacitances, reduced gate switching energies and smaller source-drain leakage currents.Comment: 4 pages including 3 figures, APL in pres

Whose absentee votes are returned and counted: The variety and use of absentee ballots in California

Absentee voting is becoming more prevalent throughout the United States. Although there has been some research focused on who votes by absentee ballot, little research has considered another important question about absentee voting: which absentee ballots are counted and which are not? Research in the wake of the 2000 presidential election has studied the problem of uncounted ballots for precinct voters but not for absentee voters. Using data from Los Angeles County – nation's largest and most diverse voting jurisdiction – for the November 2002 general election, we test a series of hypotheses that certain types of voters have a higher likelihood that their ballots will be counted. We find that uniform service personnel, overseas civilians, voters who request non-English ballots and permanent absentee voters have a much lower likelihood of returning their ballot, and once returned, a lower likelihood that their ballots will be counted compared with the general absentee voting population. We also find that there is little partisan effect as to which voters are more likely to return their ballots or have their ballots counted. We conclude our paper with a discussion of the implications of our research for the current debates about absentee voting

Are Americans confident their ballots are counted?

Building on the literature that investigates citizen and voter trust in government, we analyze the topic of voter confidence in the American electoral process. Our data comes from two national telephone surveys where voters were asked the confidence they have that their vote for president in the 2004 election was recorded as intended. We present preliminary evidence that suggests confidence in the electoral process affects voter turnout. We then examine voter responses to determine the overall level of voter confidence and analyze the characteristics that influence the likelihood a voter is confident that their ballot was recorded accurately. Our analyses indicate significant differences in the level of voter confidence along both racial and partisan lines. Finally, we find voter familiarity with the electoral process, opinions about the electoral process in other voting precincts, and both general opinions about voting technology and the specific technology the voter uses significantly affect the level of voter confidence

Reply to Comment by Galapon on 'Almost-periodic time observables for bound quantum systems'

In a recent paper [1] (also at http://lanl.arxiv.org/abs/0803.3721), I made several critical remarks on a 'Hermitian time operator' proposed by Galapon [2] (also at http://lanl.arxiv.org/abs/quant-ph/0111061). Galapon has correctly pointed out that remarks pertaining to 'denseness' of the commutator domain are wrong [3]. However, the other remarks still apply, and it is further noted that a given quantum system can be a member of this domain only at a set of times of total measure zero.Comment: 3 page

Strength of fracture zones from their bathymetric and gravitational evolution

Fracture zone evolution is investigated using dynamic models that allow the fault zones to freely slip. This is an improvement over past formulations where bathymetric offsets were imposed kinematically. The models use a viscoelastoplastic rheology that incorporates the influence of fault friction on fracture zone slip history. Using viscoelastic plates, we assess the role of small-scale convection on removal of the lowermost thermal lithosphere beneath fracture zones. Through a comparison of synthetic gravity to free-air gravity across fracture zones we find that the amplitude of the gravity jump across fracture zones is best fit by models with weak faults that have depth-averaged yield strengths <10 MPa. Fracture zones with such low strengths can convert to subduction zones with ∼100 km of convergence. Many fracture zones do not fit plate subsidence models with locked or slipping faults but are better fit by systems that are tectonically deformed by modest amounts of extension

The complexity of the California recall election

The October 7, 2003 California Recall Election strained California’s direct democracy. In recent California politics there has not been a statewide election conducted on such short notice; county election officials were informed on July 24 that the election would be held on October 7. Nor has California recently seen a ballot with so many candidates running for a single statewide office (see Mueller 1970). Under easy ballot access requirements, Secretary of State Kevin Shelley certified 135 candidates for the official ballot on August 13^1. In the recall, voters cast votes on (1) whether to recall Governor Davis from office, and (2) his possible successor. These two voting decisions were made independent by the federal district court’s decision on July 29. The court’s decision invalidated a state law requiring a vote on the recall question in order for a vote on the successor election to be counted (Partnoy et al. 2003). The abbreviated election calendar also led to many improvisations, including a dramatically reduced number of precinct poll sites throughout the state and the unprecedented ability of military personnel, their dependents, and civilians living overseas to return their absentee ballots by fax. These problems produced litigation and speculation that substantial problems would mar the election and throw the outcome of both the recall and a possible successor’s election into doubt. In the end, the litigation failed to stall the recall election, and the large final vote margins on both the recall question and the successor ballot seemingly overwhelmed Election Day problems. In this paper, we concentrate on some of the problems produced by the complexity of the recall election, but we do not attempt an exhaustive presentation of these problems. We focus on polling place problems on election day, the problems associated with translating the complicated recall election ballot into six languages, how the long ballot influenced voter behavior, and voter difficulties with the ballot measured with survey data. We conclude with a short discussion of the possible impact of these problems on the recall election

Lessons and Trends in E-Voting: Initiatives in the U.S. and Abroad

Since the 2000 election, there has been a debate over the role of voting technology in the election process. In 2000 and 2001, this debate focused on the deficiencies associated with paper ballots—especially the punch card—and the ballot errors associated with these ballots. However, this debate has shifted since 2002 to a conflict between concerns about the accessibility of voting technologies versus their security, especially electronic voting technologies. This shift in the debate over voting technologies can be seen in the quantity and tone of media coverage of this issue, with coverage swinging markedly against electronic voting in 2003 and 2004. The accessibility versus security debate is familiar ground for interest groups, scholars, and players in the election policy domain. Similar debates previously occurred over modification of voter registration and related voter access issues

Rational and Pluralistic Approaches to HAVA Implementation

The Help America Vote Act (HAVA) has created a new dynamic for the oversight and implementation of federal elections, requiring states to assume greater control of election processes vis-a-vis their local governments than was previously the case in most states. We consider how HAVA has changed the relationship between states and localities, especially through the HAVA planning process. We examine two approaches that states have used in HAVA planning—a rational approach and a pluralistic approach—and how each can shape the power relationship between states and localities. We then present case studies from Georgia and California to illustrate how these two approaches have functioned in practice