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排序方式: 共有447条查询结果,搜索用时 15 毫秒
31.
The cost of quality assurance programs in asphalt road construction is high in part because of the need for daily testing. This paper demonstrates the methodology used to investigate the timing of sampling and its effect on the quality assurance program. Fourteen lots over two highway paving projects were tested twice: during construction on a daily basis, and after construction was complete. Three quality measures were compared, namely asphalt content, degree of compaction, and aggregate gradation. The test data during construction were obtained from two sources: the consultant’s quality assurance, and the contractor’s quality control. One-way ANOVA tests and T-tests were used to compare the means. In addition, the arithmetic difference between the means was reviewed to understand how the time of sampling might affect contractor payment adjustments. 相似文献
32.
Peter MA Toivonen Paul A Wiersma Cheryl Hampson Brenda Lannard 《Journal of the science of food and agriculture》2010,90(4):580-585
BACKGROUND: One of the realities of apple distribution for long‐term stored fruit is that a controlled‐atmosphere (CA) storage room will be unsealed and fruit held in air storage and marketed over several weeks. This work was conducted to determine the effect of post‐CA air storage of whole fruit on potential shelf life for fresh‐cut apple slices. RESULTS: Fresh‐cut slices of ‘Spartan’ and ‘Delicious’ apples held in post‐CA air storage for 2 or 4 weeks showed the least changes in cut surface color as compared with those made from apples immediately on removal from CA. Shelf life was most improved by post‐CA air storage in the ‘Spartan’ apples, which were more advanced in maturity as compared with the ‘Delicious’ apples. Internal ethylene concentration, firmness, and respiration changed significantly with post‐CA air storage, suggesting a relationship between physiological status of the whole fruit and shelf life of slices made from that fruit. CONCLUSION: The results support the hypothesis that apples had suppressed physiological activity in CA storage and are susceptible to accelerated deterioration upon cutting. Holding fruit for 2 weeks in air storage allowed recovery of physiological activity, which resulted in greater resistance to deterioration in response to fresh‐cut processing. Copyright © 2010 Crown in the right of Canada. Published by JohnWiley & Sons, Ltd 相似文献
33.
Kling Kristen C.; Hyde Janet Shibley; Showers Carolin J.; Buswell Brenda N. 《Canadian Metallurgical Quarterly》1999,125(4):470
Two analyses were conducted to examine gender differences in global self-esteem. In Analysis I, a computerized literature search yielded 216 effect sizes, representing the testing of 97,121 respondents. The overall effect size was 0.21, a small difference favoring males. A significant quadratic effect of age indicated that the largest effect emerged in late adolescence (d?=?0.33). In Analysis II, gender differences were examined using 3 large, nationally representative data sets from the National Center for Education Statistics (NCES). All of the NCES effect sizes, which collectively summarize the responses of approximately 48,000 young Americans, indicated higher male self-esteem (ds ranged from 0.04 to 0.24). Taken together, the 2 analyses provide evidence that males score higher on standard measures of global self-esteem than females, but the difference is small. Potential reasons for the small yet consistent effect size are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
When taking multiple-choice tests of reading comprehension such as the Scholastic Assessment Test (SAT), test takers use a range of strategies that vary in the extent to which they emphasize reading the questions versus reading the passages. Researchers have challenged the construct validity of these tests because test takers can achieve better-than-chance performance even if they do not read the passages at all. By using an individual-differences approach that compares the relative power of working memory span to predict SAT performance for different test-taking strategies, the authors show that the SAT appears to be tapping reading comprehension processes as long as test takers engage in at least some reading of the passages themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Major Brenda; Cozzarelli Catherine; Sciacchitano Anne Marie; Cooper M. Lynne; Testa Maria; Mueller Pallas M. 《Canadian Metallurgical Quarterly》1990,59(3):452
Prior to their having a 1st trimester abortion, women's perceptions of social support from their partner, family, and friends and self-efficacy for coping were assessed. Depression, mood, physical complaints, and anticipation of negative consequences were measured after the 30-min recovery period. As predicted, perceived social support enhanced adjustment indirectly through its effects on self-efficacy. Women who perceived high support from their family, friends, and partners had higher self-efficacy for coping. Higher self-efficacy, in turn, predicted better adjustment on the psychological measures but not on the physical complaint measure. No direct path between social support and adjustment was observed. In addition, women who told close others of their abortion but perceived them as less than completely supportive had poorer postabortion psychological adjustment than either women who did not tell or women who told and perceived complete support. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
David R. McLean Brenda J. Page Alan Tuchman Andrew V. Kispert Wen L. Yen
William J. Potter
《Expert systems with applications》1992,5(3-4):441-446Classical planning systems attempt to solve a planning problem by avoiding possible conflicts before the actions are put on a timeline. This is computationally very expensive and the search for all possible future conflicts may be prohibitive. A conflict resolution approach can check for immediate conflicts and try conflict resolution strategies as each activity is put on a timeline without regard for possible future conflicts. A more practical approach is to use a combination of conflict avoidance and conflict resolution based upon heuristics which limit the amount of search required when either is used. Because humans are not good at solving problems which require complex lookahead, this combined approach, with emphasis on conflict resolution, is what human schedulers actually use when they develop schedules. A system which simulates this human approach to scheduling has been developed at NASA's Goddard Space Flight Center for scheduling satellite activities. This system, which includes the Planning And Resource Reasoning (PARR) shell, allows expert schedulers to specify conflict resolution strategies as well as conflict avoidance strategies to be used during the scheduling process. PARR has been used since May 1987 to schedule the Tracking and Data Relay Satellite System services for the Earth Radiation Budget Satellite. PARR will also be used to schedule platform resources on the Explorer Platform, scheduled for launch in early 1992. This paper describes the advantages of using a combined conflict avoidance and resolution approach in a satellite scheduling system. 相似文献
37.
Adler Nancy E.; David Henry P.; Major Brenda N.; Roth Susan H.; Russo Nancy Felipe; Wyatt Gail E. 《Canadian Metallurgical Quarterly》1992,47(10):1194
Psychological research is increasingly involved in debates regarding abortion. While recognizing the diversity of ethical and moral issues intertwined with abortion, the American Psychological Association (APA) has focused its involvement on psychological factors, most recently by appointing an expert panel to review the literature on psychological effects. This article notes the history of APA involvement and reports on the panel's conclusions. It presents evidence that abortion is not likely to be followed by severe psychological responses and that psychological aspects can best be understood within a framework of normal stress and coping rather than a model of psychopathology. Correlates of more negative responses following abortion are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
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40.
Chow CF Kong HK Leung SW Chiu BK Koo CK Lei EN Lam MH Wong WT Wong WY 《Analytical chemistry》2011,83(1):289-296
Gaseous biogenic amines such as putrescine, spermidine, aniline, and trimethylamine are important biomolecules that play many crucial roles in metabolism and medical diagnostics. A chemodosimetric detection assay has been developed for those gaseous amines by Ru(II)-Eu(III) heterobimetallic complexes, K{[Ru(II)((t)Bubpy)(CN)(4)](2)Eu(III)(H(2)O)(4)} (where (t)Bubpy = 4,4'-di-tert-butyl-2,2'-bipyridine). Synthesis, X-ray crystal characterization, and spectroscopic properties of this Ru(II)-Eu(III) heterobimetallic complex were reported. Binding properties of the Ru(II)-Eu(III) complex with common gases revealed that this complex is very selective to gaseous amine molecules. Sensitivity of this complex toward the amines was found as ~log k() = 4.5-4.8. Real time monitoring of gaseous biogenic amines was applied to real fish samples (Atlantic mackerel) by studying the spectrofluorimetric responses of the Ru(II)-Eu(III) complex toward different biogenic amine concentration. GC/MS studies were also used as a reference for the studies. A linear spectrofluorimetric response was found toward biogenic amine concentration in real fish samples. This complex was found to respond specifically to those biogenic amines down to 10 ppb. 相似文献