Method of detecting oxygen in a gas

The presence of oxygen in a gas is detected by contacting an article, such as a film, comprising poly(ethylenenaphthalene-dicarboxylate) with a gas and simultaneously exposing the article to ultraviolet light. The article is subsequently heated and the presence of oxygen in the gas is indicated by thermoluminescence

Resolution changes in lithium-drifted silicon semiconductor detectors irradiated with 0.5, 1.0, 2.0, and 3.0 MeV electrons

Electron irradiation effect on resolution of lithium-drifted silicon semiconductor detector

Determinants of the Timing and Incidence of Exploratory Drilling on Offshort Wildcat Tracts

This paper documents exploratory drilling activity on offshore wildcat oil and gas leases in the Gulf of Mexico that were sold between 1954 and 1990, with emphasis on the period before 1980. For each year of the lease, we study the determinants of the decision whether or not to begin exploratory drilling, and the outcome of any drilling activity. Our results indicate that equilibrium predictions of plausible noncooperative models are reasonably accurate, and more descriptive than those of cooperative models of drilling timing. We discuss why noncooperative behavior may occur, and the potential gains from coordination.

Empirical Implications of Equilibrium Bidding in First-Price, Symmetric, Common Value Auctions

This paper studies federal auctions for wildcat leases on the Outer Continental Shelf from 1954 to 1970. These are leases where bidders privately acquire (at some cost) noisy, but equally informative, signals about the amount of oil and gas that may be present. We develop a test of equilibrium bidding in a common values model that is implemented using data on bids and ex post values. We compute bid markups and rents under the alternative hypotheses of private and common values and find that the data are more consistent with the latter hypothesis. Finally, we use data on tract location and ex post values to test the comparative static prediction in common value auctions that bidders may bid less aggressively when they expect more competition.

Fluorinated monomers useful for preparing fluorinated polyquinoline polymers

A new class of polymers is provided, as well as the monomers used for their preparation. The polymers provided in accordance with practice of the present invention include repeating units comprising one or more quinoline groups, wherein at least a portion of the repeating units includes a hexafluoroisopropylidene (6F) group or a 1-aryl-2,2,2-trifluoroethylidene (3F) group, or both. The hexafluoroisopropylidene group is referred to herein as a 6F group and has the following structure: ##STR1## The 6F group includes a tetravalent carbon atom bound to two trifluoromethyl moieties, with its other two bonds forming linkages in the polymer chain. The 1-aryl-2,2,2-trifluoroethylidene group is referred to herein as a 3F group and has the following structure: ##STR2## wherein Ar' is an aryl group

Approximate Bayesian Computation in Forensic Science

Forensic evidence is often an important factor in criminal investigations. Analyzing evidence in an objective way involves the use of statistics. However, many evidence types (i.e., glass fragments, fingerprints, shoe impressions) are very complex. This makes the use of statistical methods, such as model selection in Bayesian inference, extremely difficult. Approximate Bayesian Computation is an algorithmic method in Bayesian analysis that can be used for model selection. It is especially useful because it can be used to assign a Bayes Factor without the need to directly evaluate the exact likelihood function - a difficult task for complex data. Several criticisms of ABC (specifically when used for model choice) can be found in the literature, yet the potential benefits of the method warrant study of the performance under controlled situations. This paper explores the use of ABC in forensic science through use of a glass example. The ABC approximation of the Bayes Factor provided the correct direction of support in the majority of known cases in the glass example. However, the approximations did not agree with the weight of support given by analytical Bayes Factors. Exploration of the inconsistent portion of results uncovered an issue with the method used to choose a threshold value in ABC. A novel method, based on a relationship between the ABC Bayes Factor and the Receiver Operating Characteristic curve, was developed to address this issue. This method produced more stable results than the traditional ABC methodology