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61.
Fisher DL Laurie NE Glaser R Connerney K Pollatsek A Duffy SA Brock J 《Human factors》2002,44(2):287-302
Driver education classes were once seen as a remedy for young drivers' overinvolvement in crashes, but research results from the early 1970s were disappointing. Few changes in the content or methods of instruction occurred until recently, but this could change rapidly. Personal computers (PCs) can now present videos or photorealistic simulations of risky, cognitively demanding traffic scenarios that require quick responses without putting the participant at risk. As such programs proliferate, evaluating their effectiveness poses a major challenge. We report the use of a fixed-base driving simulator to study the effects of both experience on the road and PC-based risk awareness training on younger drivers' part-task simulator driving performance in risky traffic scenarios. We ran three groups of drivers on the simulator: one group first trained on the PC (younger, inexperienced drivers) and two groups who received no PC training (younger, inexperienced and experienced drivers). Overall, the younger, inexperienced drivers who were trained on a PC operated their vehicles in risky scenarios in ways that differed measurably from those of the untrained younger, inexperienced drivers and, more important, in ways that we believe would decrease their exposure to risk considering that, on average, their behavior was more similar to the behavior of the untrained, experienced drivers. More research is needed to demonstrate whether these findings apply on the open road to the larger population of younger drivers. However, at least initially, the research suggests that PC-based risk awareness training programs have the potential to reduce the high crash rate among younger, inexperienced drivers. 相似文献
62.
Killen Joel D.; Fortmann Stephen P.; Murphy Greer M. Jr.; Hayward Chris; Arredondo Christina; Cromp DeAnn; Celio Maria; Abe Laurie; Wang Yun; Schatzberg Alan F. 《Canadian Metallurgical Quarterly》2006,74(2):286
The authors present results of a randomized clinical trial of the efficacy of extended treatment with bupropion SR in producing longer term cigarette smoking cessation. Adult smokers (N = 362) received open-label treatment (11 weeks) that combined relapse prevention training, bupropion SR, and nicotine patch followed by extended treatment (14 weeks) with bupropion SR or matching placebo. Abstinence percentages were relatively high (week 11: 52%; week 25: bupropion, 42%; placebo, 38%; week 52: bupropion, 33%; placebo, 34%), but bupropion SR did not surpass placebo. Gender and baseline craving level were identified as significant, independent moderators of treatment response. Men were more likely to abstain than women (week 11: 59% vs. 43%, p = .001; week 25: 48% vs. 31%, p = .001; week 52: 39% vs. 27%, p = .01). Because most smokers suffer relapse with any current cessation treatment, the comparatively high abstinence percentages achieved in this trial are of interest. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Faulty inhibition is theorized to be a central feature in attention-deficit/hyperactivity disorder (ADHD), but it remains unclear whether inhibitory impairments encompass both motoric and attentional domains. Further, characterization of inhibitory deficits in adults with ADHD is needed. We experimentally assessed adults who met diagnostic criteria for ADHD and a subgroup who had partially remitted. Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) subtype effects were also examined. Motoric inhibition was assessed with the antisaccade task, and attentional inhibition was assessed with the attentional blink (AB) task. Antisaccade results replicated prior findings of extended latencies and increased anticipatory saccades in ADHD. Errors, however, appeared to be epiphenomenal to ADHD as they were absent when symptoms had partially remitted. Anticipatory saccades appeared as potential core problems that remained even when symptoms had improved. Differential response patterns were found for predominantly inattentive and combined subtypes, with the latter showing increasing anticipatory movements with increasing fixation time. In the AB task, ADHD groups committed more errors but showed no convincing evidence of an abnormal blink. These results demonstrate clear effects on motoric inhibition but not attentional inhibition in adults with ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
65.
Conner D.C. Greenfield A. Atkar P.N. Rizzi A.A. Choset H. 《Automation Science and Engineering, IEEE Transactions on》2005,2(4):381-392
This research is focused on developing trajectory planning tools for the automotive painting industry. The geometric complexity of automotive surfaces and the complexity of the spray patterns produced by modern paint atomizers combine to make this a challenging and interesting problem. This paper documents our efforts to develop computationally tractable analytic deposition models for electrostatic rotating bell (ESRB) atomizers, which have recently become widely used in the automotive painting industry. The models presented in this paper account for both the effects of surface curvature as well as the deposition pattern of ESRB atomizers in a computationally tractable form, enabling the development of automated trajectory generation tools. We present experimental results used to develop and validate the models, and verify the interaction between the deposition pattern, the atomizer trajectory, and the surface curvature. Limitations of the deposition model with respect to predictions of paint deposition on highly curved surfaces are discussed. Note to Practitioners-The empirical paint deposition models developed herein, which are fit to experimental data, offer a significant improvement over models that are typically used in industrial robot simulations. The improved simulation results come without the computational cost and complexity of finite element methods. The models could be incorporated, as is, into existing industrial simulation tools, provided the users are cognizant of the model limitations with respect to highly curved surfaces. Although the models are based on readily available information, incorporating the models into existing robot simulation software would likely require support from the software vendor. 相似文献
66.
David A. Conner Ph.D. P.E. Gary J. Grimes Ph.D. Jay Goldman D.SC. P.E. 《Journal of Systems Integration》2000,10(1):81-94
For telemedicine to reach its potential in the Internet2 environment,significant progress must be made in a number of areas. The emergingtelecommunications will include the Internet2 between medicalinstitutions and emerging broadband loop and wireless technologiesfor interconnections to homes. Within the technical environment,problems that must be addressed include the development of robotic-controlled,remote-monitoring devices unique to the various medical specialties;the encoding, transmission, and decoding of raw data specificto the specialized needs of various medical application areas;and the reduction of data for storage and retrieval in patientrecords. Institutionally, human factor and information accessissues with respect to physicians, patients, and non-physicianhealthcare providers must be addressed; healthcare insuranceprovider policies, government regulation, and state licensinglaws must be adapted for a new paradigm of healthcare delivery;and the philosophy of capital investment for the delivery ofhealthcare must be revised.Many current practiceswill be supplanted by home healthcare alternatives, the use ofpatient-initiated preventive healthcare initiatives, and remote-clinicactivity. These applications will result in central record archivingsystems; the need for encryption schemes, virus protection, andvandalism protection; extensive, additional connectivity betweenhealthcare providers and professionals; and new commercial playersin the healthcare arena.The hot applicationareas will include women's health, children's health, healthcarefor senior citizens, home healthcare, well-patient monitoring,and early-detection of medical problems. 相似文献
67.
Ninety-six weanling pigs (initial BW = 9.3 kg, initial age = 37 d) were used in a 4-wk experiment to evaluate the response to three Ca: total (t) P ratios (1.2:1, 1.6:1, or 2.0:1) fed in combination with two P levels (.07 or .16% available that correspond to .36 or .45% tP) and two phytase levels (PY; 700 or 1,050 units/kg of diet). A 3 x 2 x 2 factorial arrangement of treatments was employed using a corn-soybean meal diet. Performance, serum mineral concentrations and alkaline phosphatase (ALP) activity, Ca and P digestibility and excretion, and bone mechanical measurements were examined. Average daily gain (P < .001), average daily feed intake (P < .01), and gain:feed (P < .05) were decreased linearly as the Ca:tP ratio became wider. The digestibility of P and Ca were decreased (P < .001) linearly as the Ca:tP ratio became wider. The digestibility of P (P < .001) and fecal P excretion (P < .01) were increased at the higher level of P. Increasing PY from 700 to 1,050 units (U)/kg of diet increased (P < .05) P digestibility and decreased (P < .01) P excretion but did not improve bone measurements. Shear force, stress and energy, and percentage of ash of both metacarpal and 10th rib linearly decreased (P < .001 to .05) as the Ca:tP ratio became wider, and bone measurements were generally greater for pigs fed the higher P level. Serum Ca concentration increased (P < .01) and the P concentration decreased (P < .001) as the Ca:tP ratio increased, but Mg, Zn, and ALP activity were not influenced by the Ca:tP ratio. Serum Ca and P concentrations were affected by PY supplementation over the 4-wk trial, but serum Mg and Zn concentrations were not affected by dietary treatments. Adverse effects of a wide Ca:tP ratio were greater at the low P diet for all responses. In addition, the activity of supplemental PY in diets seemed to be decreased as the Ca:tP ratio became wider and this negative effect of Ca:tP ratio seemed greater at the low P level, and seemed to parallel the effects of Ca:tP ratio on performance, P digestibility, bone, and serum measurements. Narrowing the dietary Ca:total P ratio from 2.0:1 to 1.2:1 led to an approximate 16% increase in phytase efficacy for improving performance, digestibility, bone measurements, and serum Ca levels. 相似文献
68.
This study tested Hispanic ethnicity and parent alcoholism as moderators of pubertal status effects on the parent-child relationship in a community sample of 421 boys and girls 11.5-16.5 years old. Ethnicity was a significant moderator: The direction of the puberty effect on parent support and parent-adolescent conflict differed for Hispanic (primarily Mexican American) and non-Hispanic White boys. Parent alcoholism did not moderate the effect of puberty, but there was more conflict and less support between children of alcoholics and their parents than between controls and their parents. Puberty effects on the parent-adolescent relationship were also found above and beyond the effects of chronological age. Future directions for research in this area are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
The purpose of this study was to investigate how headache sufferers and headache-free controls differ in their responses to acute pain. Thirty-three women completed the study (15 headache sufferers and 18 controls). The cold pressor was used to induce pain, and a partially inflated blood pressure cuff was used as a nonpainful comparison task. Headache sufferers reported more discomfort during both tasks; however, the 2 groups did not differ in the number of facial expressions of pain displayed during the tasks. Headache sufferers reported a tendency to catastrophize during both tasks; positive coping did not differ between the groups. These results offer evidence that recurrent tension headache sufferers are more sensitive to both painful and nonpainful stimuli and that they cope differently from controls with these physical stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Naditch Murray P.; Gargan Margaret A.; Michael Laurie B. 《Canadian Metallurgical Quarterly》1975,84(1):1
Reformulated a number of clinical observations about depression to test them empirically, using multiple regression equations. Ss were 547 men in Army basic training. Psychological measures included the Depression subscale of the Cornell Medical Index, Rotter's Internal-External Control Scale, the Institute for Personality and Ability Testing Anxiety Scale, N. Hahn's denial measure, and the Cantril Self-Anchoring Striving Scale. Depression was negatively correlated with denial and positively correlated with anxiety, locus of control, and the discrepancy between aspirations and achievements (discontent). Locus of control was positively correlated with discontent and anxiety and negatively correlated with denial. There were interaction effects between locus of control and discontent, between locus of control and anxiety, and between anxiety and denial when these terms were regressed on depression. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献