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1.
Graduated driver licensing (GDL) programs are specialized licensing systems for beginner drivers adopted in all U.S. states, Australia, Canada, and New Zealand. GDL programs reduce novice drivers’ exposure to high-risk driving situations while they gain driving experience. Several studies document the success of GDL programs overall in reducing young teen crash rates. However, little is known about which specific components of these programs (e.g., nighttime driving restrictions) and which calibrations of these components (e.g., 10 PM, 11 PM, 12 AM, or 1 AM), are associated with the largest crash reductions. The goal of this study was to identify the GDL component calibrations associated with the largest reductions in fatal crash involvements for 16–17-year-olds. Driver fatal crash involvements for all U.S. states from 1986 to 2007 were analyzed using Poisson regression models to estimate the association of various GDL component calibrations with 16- and 17-year-old driver fatal crash incidence, after adjusting for potential confounders. We found clear evidence that (a) a minimum learner permit holding period of 9–12 months and (b) a passenger restriction allowing only one teen passenger for 6 months or longer are the calibrations for the learner permit holding period and passenger restriction components associated with the largest reductions in 16–17-year-old driver fatal crash involvements. Additionally, the data suggest that (a) disallowing learner driving until age 16, (b) disallowing intermediate licensure until age 16½ to 17, and (c) a nighttime driving restriction starting at 10 PM or earlier are the calibrations for these components associated with the largest reductions in 16-year-old driver fatal crashes. There was no clear evidence to support particular calibrations for supervised driving hours or unrestricted license ages.  相似文献   
2.
The use of computer‐based technology is becoming more prevalent in the classroom. As a part of an educational research project sponsored by the GE Foundation, strategies for augmenting a course, Introduction to Environmental Engineering (CE 280), were investigated including cross‐disciplinary experiences in teamwork, design, and the use of advanced teaching technologies such as the web. Interactive tools to assist student learning were developed and refined. Efforts have focused on developing an extensive website, web‐based quizzes and homework assignments, and tutorials. Base groups were used to provide both intellectual and emotional support to students. This paper summarizes the development of this course and the impact of rapid feedback on the progression of student understanding.  相似文献   
3.
Balance-sheet data offer a potentially large number of candidate predictors of corporate financial failure. In this paper we provide a novel predictor selection procedure based on non-parametric regression and classification tree method (CART) and test its performance within a standard logit model. We show that a simple logit model with dummy variables created in accordance with the nodes of estimated classification tree outperforms both standard logit model with step-wise-selected financial ratios, and CART itself. On a population of Slovenian companies our method achieves remarkable rates of precision in out-of-sample bankruptcy prediction. Our selection method thus represents an efficient way of introducing non-linear effects of predictor variables on the default probability in standard single-index models like logit. These findings are robust to choice-based sampling of estimation samples.  相似文献   
4.
Presents the citation and biography for Norman Garmezy, recipient of the American Psychological Association's Gold Medal Award for Life Contribution by a Psychologist in the Public Interest. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Personality and competence were examined in a community sample of 205 children ages 8-12 yrs old who were followed up 10 yrs later in emerging adulthood (ages 17-23 yrs old). Adult Positive Emotionality (PEM), Negative Emotionality (NEM), and Constraint (CON) were presaged by childhood personality. PEM was associated with current success in social and romantic relationships. Low CON was associated with childhood and current antisocial conduct. NEM was broadly linked to childhood and current maladaptation, consistent with the possibility that failure in major developmental tasks increases NEM. Findings highlight the pervasive linkage of NEM to maladaptation and suggest that adult personality may develop from processes embedded in childhood adaptation as well as childhood personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Jatropha curcas is a well-known source of non-edible vegetable oil that is being promoted as an energy source and high quality feedstock in biodiesel production, especially in developing countries. The potential that the resulting seedcake by-product from jatropha oil extraction (?70% by volume) could also be used as a component in animal feed raises the prospect that a commercially viable jatropha-based industry could be developed. To date, however, the use of jatropha seedcake in livestock feed formulation has been constrained by the presence of phorbol esters (PE), which are known promutagenic and toxic compounds, and by the inability to eliminate PE by cost-effective means. Using seedcake by-product collected from a commercial facility in West Africa that processes jatropha biodiesel, this study demonstrates cost-effective measures of eliminating PE from jatropha seedcake using a combination of solar irradiation and ozonation.  相似文献   
7.
Norman Garmezy, a pioneer in research on risk and resilience, died in Nashville, Tennessee, on November 21, 2009, at the age of 91. He was a legendary mentor as well as an eminent scientist in clinical psychology. Norm was born on June 18, 1918, in New York City and grew up in the Bronx in a Jewish neighborhood where educational attainment was highly valued. The scientific study of resilience as conceived by Norman Garmezy, his peers, and students has transformed the science and practice of multiple disciplines, from the molecular level to the global ecosystem, infusing a strength-based and recovery-oriented approach into psychology, education, social work, and psychiatry. Current research on resilience ranges from studies of plasticity in brain development to effective planning for resilience in the context of disaster. Norm’s influential ideas and research earned him international acclaim and many honors for lifetime achievements in science. Throughout his career, Norm held many leadership roles. Throughout his life, Norm spoke with great love about his wife of 63 years, Edie Garmezy (who died just months before him in 2009), and their children. In addition to his work and his family, Norm had three abiding passions—theater, movies, and politics. During the last two decades of his life, Norm and those who loved him endured his long decline from Alzheimer’s, which slowly stole his brilliant mind and hilarious sense of humor. Nonetheless, the incredible spirit and humanity of this giant scholar continued to shine through this terrible disease. To the end of his life, Norm’s face would light up with a smile as he greeted the people he loved, and he would often exclaim, “Wonderful!” Norman Garmezy was a remarkable person and scholar who left an extraordinary legacy of love and work to inspire future generations in their efforts to understand and promote the human capacity for competence and resilience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The removal of disinfection byproducts and their precursors was investigated using a combined ozonation-ultrafiltration system. A commercial membrane was coated 20 or 40 times with iron oxide nanoparticles (4-6 nm in diameter). With this membrane, the concentration of dissolved organic carbon was reduced by >85% and the concentrations of simulated distribution system total trihalomethanes and simulated distribution system halo acetic acids decreased by up to 90% and 85%, respectively. When the coated membrane was used, the concentrations of aldehydes, ketones, and ketoacids in the permeate were reduced by >50% as compared to that obtained with the uncoated membranes. Hydroxyl or other radicals produced at the iron oxide coated membrane surface as a result of ozone decomposition are believed to have enhanced the degradation of the natural organic matter, thereby reducing the concentration of disinfection byproducts. While increasing the number of times the membrane was coated from 20 to 40 did not significantly reduce the concentrations of most of the parameters measured, it did result in a significant decrease in the concentrations of ozonation byproducts. Increasing the sintering temperature from 500 to 900 degrees C also resulted in an improvement in the removal of the ozonation byproducts.  相似文献   
9.
Evaluation of biodegradability of NOM after ozonation   总被引:1,自引:0,他引:1  
Yavich AA  Lee KH  Chen KC  Pape L  Masten SJ 《Water research》2004,38(12):2839-2846
The major purpose of this study was to develop a simple procedure to describe the kinetics of biodegradation of natural organic matter (NOM) in drinking water and to use this procedure to evaluate changes in the concentration of biodegradable organic matter during ozonation and biotreatment. The proposed approach quantitatively describes the formation and removal of rapidly and slowly biodegradable fractions of NOM. This study showed that, depending on source water, ozonation of NOM may result in either minimal formation of biodegradable organic carbon (BDOC), or the formation of predominantly rapidly biodegradable NOM, or in the formation of both rapidly and slowly biodegradable NOM. The kinetic data obtained in this study suggest that while conventional biofiltration processes are capable of removing the rapidly biodegradable fraction, slowly biodegradable organic matter would remain in the filter effluent and may cause bacterial regrowth in the distribution system. An addition of a small amount of easily biodegradable carbon ("stimulated" biodegradation) to ozonated water appears to be effective for the removal of slowly biodegradable organic matter.  相似文献   
10.
The adaptive control literature contains hundreds of technical papers on many different approaches to the subject. However, engineers who are not specialists in adaptive theory often have difficulty selecting which approach to use in any given problem. This series of papers addresses this situation by defining a set of standard problems which are then solved by several distinct approaches to adaptive control. This introductory paper defines the problems and guidelines which have been used in this process.  相似文献   
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