5,760 research outputs found
A semi-analytic calculation on the atmospheric tau neutrino flux in the GeV to TeV energy range
We present a semi-analytic calculation on the atmospheric tau neutrino flux
in the GeV to TeV energy range. The atmospheric flux is calculated
for the entire zenith angle range. This flux is contributed by the oscillations
of muon neutrinos coming from the two-body decays and the three-body
decays, and the intrinsic tau neutrino flux surviving the
oscillations. The uncertainties in our calculations are discussed in detail.
The implications of our result are also discussed.Comment: Revtex, 30 pages (including 13 figures); paper expanded and title
slightly changed, to appear in Astroparticle Physic
Pension Incentives and Premature Retirement
This is a study of people’s retirement timing under defined benefit pension plans (DB plans). The actuarial structure of DB pensions generally creates strong incentive for people to stay with their employers, at least to their early retirement ages, not to retire beforehand. Upon tracking respondents covered by DB plans in the Wave I (1992 cohort) of the Health and Retirement Study (HRS) until they left their 1992 employers, we found that a significant percentage of people (about 17%) left their jobs prior to their early retirement ages. Why did people leave prematurely? Several possible hypotheses were considered and examined. Through simple tabulation analyses, we found that workers in the early-leaving group tend to have significantly smaller pension benefits and significantly poorer knowledge about their pensions. The impact of self-reported health status and early retirement windows were not evident. Logistic regressions showed that conditional on age dummies, pension size, and having basic pension knowledge was strongly negatively correlated to premature departure. Both excellent and poor health statuses correlate positively with early departure. Accepting an early-out window also had a significantly positive correlation with early departure
ION TRANSPORT IN POLYMER ELECTROLYTES
Batteries with superior performance will advance many technologies, such as the field of energy storage and electrochemical devices. Traditional lithium ion batteries based on liquid electrolytes have intrinsic problems such as leaking, dendrite growth, and those problems are associated with fire or even explosion hazard. Extensive efforts have been devoted into the development of solid polymer electrolytes (SPEs), which would not only reduce the size and weight of the batteries, but also solve safety related issues. However, none of current dry SPEs have reached the desired conductivity of 10-3 [0.001] S/cm at ambient temperature. The ion conductivity is controlled by two parameters, the free ion concentration and ion diffusivity. Despite the generally accepted theory that ion diffusion is facilitated by the segmental relaxation of the polymer, the mechanism of ion transport in SPEs is not completely understood.
In this dissertation, the ion transport in different SPEs systems were studied with a combination of experimental techniques: dielectric spectroscopy, differential scanning calorimetry and rheology. The ion transport mechanism was investigated in poly(propylene glycol) (PPG) doped with LiClO4 [lithium perchlorate]. A comprehensive analysis was performed by systematically varying the temperature, pressure, polymer molecular weight and salt concentration. It was found that the ion transport was controlled by the segmental relaxation of the “ion-rich” phase in the system, which obeyed the traditional theory. On the contrary, decoupling was observed in several carbonate and styrene based polymer electrolytes. Analysis indicated that the decoupling feature might be related to the packing frustration in those systems.
Polymerized ionic liquids (PolyILs) offer an opportunity of combining the high conductivity of ionic liquids and the superior mechanical strength of polymer. Unlike their small molecule analogue-aprotic ionic liquids, decoupling feature was observed in studied PolyILs. The variation of the pendant group structures altered the fragility index of the samples and thus the degree of decoupling.
Unraveling the mechanisms of the ion transport and structure-property relationship in SPEs is of obvious fundamental and industrial importance. Findings in this work suggested new routes for future polymer electrolytes design of desired properties
Judicial Proposal: The Practical Review and System Evolution of Extended Jurisdiction
The court judicial proposal has been used in the administrative justice practice more and more widely, but there is an obvious gap between the ideal prospect of system construction and the real effect. Based on the summary and analysis of the problems with the operation of the judicial proposal system in the administrative justice, this paper makes a deep reflection and discussion on the system itself, and then puts forward the approaches to promote the judicial proposal system in the administrative justice
Market Efficiency: Its Economic and Theological Implications
In finance, market efficiency, or equivalently, the Efficient Market Hypothesis, assumes that the market can transmit information completely, instantly, and freely so that asset prices reflect the fair value of the investment. An efficient market would imply that the prices were always right and that no group of investors should be able to consistently beat the market. In this article, I review the evolution of modern finance and the evidence for and against the Efficient Market Hypothesis. Decades of empirical research and historical events, such as dot-com bubble and the 2007-2008 Global Financial Crisis, resulted in a paradigm shift and made behavioral finance mainstream. I also offer some theological thoughts about finance research on this topic. I argue that our behavioral biases in investing betray our finitude, noetic effects of sin, as well as our impulse-and-intuition-driven humanity. More importantly, I argue that God is behind everything in a probabilistic way, not a deterministic way and tail events may be an important part of God’s mysterious design
Three Essays on Highways and U.S. Non-profits.
This dissertation studies highway construction in the United States in the interwar years and payments in lieu of taxes (PILOTs) that charitable nonprofit organizations pay to local governments.
The first chapter studies the impacts of Federal-Aid Highways on the evolution of retail trade in the 1920s. In the Roaring 20s, the U.S. federal government strongly encouraged state highway construction with its Federal-Aid Highway program, as a result of which state highway spending increased dramatically. The same decade saw a 36 percent decline in general stores. I offer causal evidence that these two developments were related: that increasing highway spending by 10 percent would reduce the number of general stores by 30 percent. My results speak to the decline of rural trade center during the early twentieth century and show one of the many ways that highway construction in the Interwar years literally and figuratively altered the landscape of the American economy.
The second chapter studies the impact of Federal-Aid Highways on improvements in education in U.S. South. I find that more spending on Federal Highways is associated higher per student spending in white schools, longer school year in black schools, and a widening per student spending gap between white and black schools. The spatial distribution of highway spending matches well with that of the Rosenwald school program. The evidence is consistent with the hypothesis that highway expenditure attracted external investments (in this case philanthropic investment in education), which improved educational outcomes.
The third chapter studies the determinants and the effects of payments in lieu of taxes (PILOTs). U.S. cities and towns increasingly request that nonprofits make payments in lieu of taxes (known as PILOTs). Strictly speaking, PILOTs are voluntary, though nonprofits may feel pressure to make them, particularly in high-tax communities. Evidence from Massachusetts indicates that PILOT rates, measured as ratios of payments to the value of local tax-exempt property, are higher in towns with higher property tax rates. Moreover, PILOTs appear to discourage nonprofit activity, especially their real property holdings. These patterns are consistent with voluntary PILOTs acting in a manner similar to low-rate, compulsory real estate taxes.PHDEconomicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/135822/1/econfan_1.pd
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