The Biometric Menagerie

It is commonly accepted that users of a biometric system may have differing degrees of accuracy within the system. Some people may have trouble authenticating, while others may be particularly vulnerable to impersonation. Goats, wolves, and lambs are labels commonly applied to these problem users. These user types are defined in terms of verification performance when users are matched against themselves (goats) or when matched against others (lambs and wolves). The relationship between a user's genuine and impostor match results suggests four new user groups: worms, doves, chameleons, and phantoms. We establish formal definitions for these animals and a statistical test for their existence. A thorough investigation is conducted using a broad range of biometric modalities, including 2D and 3D faces, fingerprints, iris, speech, and keystroke dynamics. Patterns that emerge from the results expose novel, important, and encouraging insights into the nature of biometric match results. A new framework for the evaluation of biometric systems based on the biometric menagerie, as opposed to collective statistics, is proposed.     

Band-gap tuning of pendant polymers for organic light-emitting devices and photovoltaic applications

The preparation of a series of novel polymers comprising pendant electro-active “push–pull” chromophores and their performance in solution-processed organic electronic devices is described. The design of the electro-active pendant chromophores was based on the well-known motif of cyano-substituted poly(p-phenylenevinylene). Optical band-gap engineering within this series of polymers was achieved by varying the conjugation length and the electron donor/acceptor functionalities of the pendant chromophores. The introduction of a cyanoimine group into the electro-active pendant module resulted in a marked narrowing of the optical band-gap compared with the other electro-active pendant chromophores investigated in this work. Bulk heterojunction solar cell devices comprising these polymers were prepared by solution processing blends of each polymer with [6,6]-phenyl-C₆₁-butyric acid methyl ester, and their performance was evaluated by measuring power conversion efficiencies. The best-performing solar cell in this series exhibited a power conversion efficiency of 0.29% and a maximum incident photon-to-current conversion efficiency of 22% and was produced using the polymer in which the electro-active chromophore comprised the cyanoimine group.     

Effect of Surface Roughness on the Oxidation Behavior of the Ni-Base Superalloy ME3

Ni-base superalloys are used in applications, such as jet aircraft engines and power production facilities that require excellent elevated temperature oxidation resistance. This present work evaluated the effect of surface roughness on the oxidation behavior of the Ni-base superalloy ME3. Isothermal oxidation tests were performed in air at different times to investigate the oxide growth kinetics. The surface oxides were also characterized using scanning electron microscopy and x-ray diffraction. The surface roughness was measured using a linear scanning profilometer. The surface roughness measurements were correlated to the oxidation rates and an empirical model is proposed to describe the effect of surface roughness on the oxidation behavior.     

Tubular shaped composites made from polythiophene covalently linked to Prato functionalized N-doped carbon nanotubes

A simple methodology to produce tubular nitrogen-doped carbon nanotube/polythiophene covalently linked composites is described. Nitrogen doped carbon nanotubes (N-CNTs) were made by the floating catalyst CVD method using toluene, ferrocene and tetramethylethylenediamine (TMEDA) as reagents. Functionalization of the N-CNTs was achieved using 3-thiophenecarboxaldehyde and N-methylglycine in 1,2-dichlorobenzene (Prato reaction). Elemental analysis showed nitrogen incorporation of N into the N-CNTs (1.8%) and also the N-methylglycine functionalized N-CNTs (f-N-CNTs; 6.2%). A series of f-N-CNT/thiophene monomer mixtures (weight ratios 1:3, 1:10 and 1:20) were used to make f-N-CNT/polythiophene tubular composites. As the amount of thiophene monomer was increased, the overall diameter of the polymer layer attached onto the N-CNTs increased. Polymer thickness also varied with reaction time (1 h, 12 h and 24 h). The combination of acid functionalization and N–doping gives the best coverage of the CNTs by polythiophene, in which the polythiophene preferentially binds to the f-N-CNTs to give tubular structures.     

Using strategic management practices to promote participatory democracy in Australian local government

Abstract

Strategic management was introduced as a critical component of Australian local government reform during the 1990s. In addition to encouraging efficiency and effectiveness of operation, it was also intended to promote participatory democracy within local authorities. The paper explores the extent to which this objective has been achieved through an analysis of twenty‐five New South Wales municipalities. Discussion concludes that while strategic management has enhanced community involvement in local governance, it cannot be a substitute for traditional democratic processes.     

Marine Water Quality Assessment Of Synthetic-Based Drilling Waste Discharges

Drilling muds or fluids used in drilling operations serve several functions: they lubricate the drill bit; maintain borehole pressure; clean and condition the hole; and flush rock cuttings to the surface. Drilling mud also adheres to rock cuttings, as can formation oil. Barite is used as a weighting agent, which approximately makes up approximately 33% of synthetic mud. It contains traces of heavy metals, which contribute to the toxicity of drilling waste. As environmental issues attract increasing public awareness, the treatment and disposal of spent drilling fluids and contaminated rock cuttings from drilling operations have become sensitive issues for offshore operations around the world. Within the last decade, the oil and gas industry has introduced synthetic-based drilling fluids as substitutes for oil-based fluids. This pollution prevention measure has been complemented by improvements in solid control systems technology. This paper adopts the current U.S. Environmental Protection Agency methodology for a hypothetical case study of an oil field on the East Coast of Canada to determine the water quality impacts of disposal of drilling wastes. The concentration of pollutants at the edge of the mixing zone in the water column and pore water are estimated and compared with Canadian water quality guidelines for protection of aquatic life.