Iris Recognition: The Consequences of Image Compression

Iris recognition for human identification is one of the most accurate biometrics, and its employment is expanding globally. The use of portable iris systems, particularly in law enforcement applications, is growing. In many of these applications, the portable device may be required to transmit an iris image or template over a narrow-bandwidth communication channel. Typically, a full resolution image (e.g., VGA) is desired to ensure sufficient pixels across the iris to be confident of accurate recognition results. To minimize the time to transmit a large amount of data over a narrow-bandwidth communication channel, image compression can be used to reduce the file size of the iris image. In other applications, such as the Registered Traveler program, an entire iris image is stored on a smart card, but only 4 kB is allowed for the iris image. For this type of application, image compression is also the solution. This paper investigates the effects of image compression on recognition system performance using a commercial version of the Daugman iris2pi algorithm along with JPEG-2000 compression, and links these to image quality. Using the ICE 2005 iris database, we find that even in the face of significant compression, recognition performance is minimally affected

Hurry up and wait : replanting decisions for pastures during drought (2009)

"Reviewed February 2009."Drought typically causes Missouri cattlemen to be concerned about their pastures. These concerns can turn to thoughts of replanting, but such plans may be premature

Long-term post-fire succession of reptiles in an urban remnant in south-western Australia

Background: Reptile responses to fire may differ between remnants and contiguous vegetation but this is poorly understood. Aims: We aimed to explore long-term (≤15 years) post-fire responses of reptiles in an urban Banksia woodland remnant. Methods: We trapped reptiles for 10 nights in November and December each year between 2009 and 2023 inclusive (except 2014 and 2019) to estimate relative abundance. We used mixed models to explore differences between unburnt and burnt sites and changes in both over time. Key results and conclusions: The reptile community showed short-term negative responses to fire, but communities had returned to their pre-fire state within 3 years. Two species showed short-term (3 and 5 years respectively) negative responses to fire while two species showed positive responses; one in the first year post-fire only, and the other in sites \u3e8 years post-fire. There did not appear to be consistent differences in fire responses between this study and studies conducted in contiguous Banksia woodlands, although differences in study designs renders this conclusion equivocal. Implications: Reptile communities in Banksia woodland remnants, and the species they contain appear to be relatively robust to a wide range of fire regimes

Synthesis and exploration of electronically modified (R)-5,5-dimethyl-(p-CF_3)_3-i-PrPHOX in palladium-catalyzed enantio- and diastereoselective allylic alkylation: a practical alternative to (R)-(p-CF_3)_3-t-BuPHOX

The synthesis of the novel electronically modified phosphinooxazoline (PHOX) ligand, (R)-5,5-dimethyl-(p-CF_3)_3-i-PrPHOX, is described. The utility of this PHOX ligand is explored in both enantio- and diastereoselective palladium-catalyzed allylic alkylations. These investigations prove (R)-5,5-dimethyl-(p-CF_3)_3-i-PrPHOX to be an effective and cost-efficient alternative to electronically modified PHOX ligands derived from the prohibitively expensive (R)-t-leucine

Mapping Low-Density Intergalactic Gas: a Third Helium Lyman-alpha Forest

We present a new HST/STIS spectrum of the z=3.18 quasar PKS 1935-692 and summarize the spectral features shortwards of 304A in the rest frame likely to be caused by foreground HeII Lyman-alpha absorption. In accord with previous results on two other quasars at similar redshifts, we demonstrate a correlation with the HI Lyman-alpha forest absorption, and show that much of the helium absorption is caused by a comparable quantity of more diffuse gas with Omega~0.01, that is not detected in HI. The helium ionization zone around the quasar is detected as well as a void seen in both HI and HeII. The properties of the absorption are in broad agreement with those of the other quasars and with models of the protogalactic gas distribution and ionization at this redshift.Comment: 17 pages including 5 figures. As accepted for publication in The Astronomical Journal (minor revisions

The Evolution of Public Sector Pension Plans in the United States

Municipal governments in the U.S. began offering retirement plans for their workers in the mid-19th century, and state governments followed in the early 20th century. As these plans matured, they confronted economic, social, and political challenges, including the creation of the Social Security system, which subsequently shaped their structure, governance, and generosity. After reviewing this history, we employ data from all 50 states to estimate a pension benefit equation for hypothetical workers and explain differences in the generosity of plans across states and types of workers covered. We show that population growth, plan funding, union representation, and participation in Social Security influenced the generosity of the plans

An Empirical Examination of Two Models of Cultural Causation

The traditional macroscopic model of cultural causation advanced by Weber and modified by Parsons assumes that values provide orientation for human action. Thus, values are conceptualized as the intervening link between culture and behavior and in general, are viewed as predictive of human action. Swidler (1986) contends that values are a poor predictor of behavior. As an a/tentative model, Swidler asserts that cultures provide actors with a limited array of behavioral options. Because this array is finite and indicative of a particular cultural setting, inuacultural behavioral similatities are observable. We empirically test the link between culture and behavior in a situation which Swidler defines as "unsettled lives." Our findings offer little support for the traditionally assumed link between values and behavior. The theoretical implications of our findings are discussed and an expansion of Swidler's model is offered

The Evolution of Mentorship Capacity Development in Low- and Middle-Income Countries: Case Studies from Peru, Kenya, India, and Mozambique.

Following the Fogarty International Center-supported "Mentoring the Mentors" workshops in South America, Africa, and Asia, approaches and guidelines for mentorship at institutions within these low- and middle-income country (LMIC) contexts, appropriate for the respective regional resources and culture, were implemented. Through the presentation of case studies from these three geographic regions, this article illustrates the institutional mentorship infrastructure before the workshop and the identified gaps used to implement strategies to build mentorship capacity at the Universidad Peruana Cayetano Heredia (Peru), Kenya Medical Research Institute (Kenya), Saint John's Research Institute (India), and Eduardo Mondlane University (Mozambique). These case studies illustrate three findings: first, that mentorship programs in LMICs have made uneven progress, and institutions with existing programs have exhibited greater advancement to their mentoring capacity than institutions without formal programs before the workshops. Second, mentoring needs assessments help garner the support of institutional leadership and create local ownership. Third, developing a culture of mentorship that includes group mentoring activities at LMIC institutions can help overcome the shortage of trained mentors. Regardless of the stage of mentoring programs, LMIC institutions can work toward developing sustainable, culturally effective mentorship models that further the partnership of early career scientists and global health

Effects of Cement Bases on the Stresses in Amalgam Restorations

A computerized dental model was used to study the stress induced in a Class 1 amalgam restoration when supported by bases of varying materials and thicknesses. Under the same load, the maximum tensile stresses and deftections in the amalgam restoration increased at least threefold with a zinc oxideeugenol base as compared with a ZnPO 4 cement base.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67330/2/10.1177_00220345750540010101.pd

Analysis Of Corn And Soybean Basis Patterns And Hedging Opportunities For Cash-Grain Producers By Price Reporting Districts In Iowa

In recent years, Iowa farmers have faced large variations in grain prices in short periods of time. Price variability stems from increased dependence on foreign markets and a wide range of world developments that affect cash grain prices. As an example of the potential impact on farmers, the variability • \u27 t \u27 ^ in 1980-crop prices during the last half of 1979 created a potential variation of $20,000 in net income from a 300 acre Central Iowa cash grain farm — depend ing on whether crops were sold at the high or low end of the range of available prices..