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101.
Data are reported from 3,213 research eyewitnesses confirming that accurate eyewitness identifications from lineups are made faster than are inaccurate identifications. However, consistent with predictions from the recognition and search literatures, the authors did not find support for the "10-12-s rule" in which lineup identifications faster than 10-12 s maximally discriminate between accurate and inaccurate identifications (D. Dunning & S. Perretta, 2002). Instead, the time frame that proved most discriminating was highly variable across experiments, ranging from 5 s to 29 s, and the maximally discriminating time was often unimpressive in its ability to sort accurate from inaccurate identifications. The authors suggest several factors that are likely to moderate the 10-12-s rule. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
The image-interpretation of opium poppy crops from very high resolution satellite imagery forms part of the annual Afghanistan opium surveys conducted by the United Nations Office on Drugs and Crime and the United States Government. We tested the effect of generalization of field delineations on the final estimates of poppy cultivation using survey data from Helmand province in 2009 and an area frame sampling approach. The sample data was reinterpreted from pan-sharpened IKONOS scenes using two increasing levels of generalization consistent with observed practice. Samples were also generated from manual labelling of image segmentation and from a digital object classification. Generalization was found to bias the cultivation estimate between 6.6% and 13.9%, which is greater than the sample error for the highest level. Object classification of image-segmented samples increased the cultivation estimate by 30.2% because of systematic labelling error. Manual labelling of image-segmented samples gave a similar estimate to the original interpretation. The research demonstrates that small changes in poppy interpretation can result in systematic differences in final estimates that are not included within confidence intervals. Segmented parcels were similar to manually digitized fields and could provide increased consistency in field delineation at a reduced cost. The results are significant for Afghanistan’s opium monitoring programmes and other surveys where sample data are collected by remote sensing.  相似文献   
103.
The objectives of this study were to examine varying extraction conditions of Thymus vulgaris L. as related to phenolic content and profiles of the extracts and their antioxidant, antihypertensive and antidiabetic properties. Phenolics were extracted under various conditions pertaining to free and bound phenolics, solvent type and combination of extraction time and temperature, and these extracts were evaluated in terms of their antioxidant activities and inhibitory activities of angiotensin‐converting enzyme (ACE), α‐glucosidase and α‐amylase. The acetone–water solvent mixture (1:1; v/v) produced the extract with the greatest phenolic content, antioxidant activity and inhibitory activities of ACE and α‐glucosidase. The optimal extraction temperature for maximum phenolic content and antioxidant activity associated with methanol extraction was 60 °C, whereas a lower temperature at 40 °C was required to maximise inhibitory activities for ACE, α‐glucosidase and α‐amylase. An inverse relationship was seen between antioxidant and glucosidase inhibitory activities vs. the ACE and α‐amylase inhibitory activities, which suggests the need for extractions to be directed to specific bioactivities of thyme extracts. Generally, the results indicate major differences in phenolic profiles among the tested extraction conditions with thymol as the predominant phenolic seen in most extractions, while gallic acid, rosmarinic acid or diosmin also predominated in other extracts. Extracts with the same predominant phenolic compound and similar phenolic content showed major disparities in their ACE, glucosidase and α‐amylase inhibitory activities, indicating that the major phenolic profiles of thyme extracts may not be necessarily related to the degree of inhibition of ACE, glucosidase and α‐amylase enzymes.  相似文献   
104.
The oxidative stability of refined olive oil with incorporated Pistacia khinjuk fruit oil (PKFO; 0.5%, 1%, 2%, 5%, and 10%) during thermal processing at 170ºC for 8 h was evaluated. The conjugated diene values, carbonyl values, acid values, oil/oxidative stability indices, and total tocopherol content were measured during thermal processing. Olive oil containing 0.5% PKFO was identified as the most oxidative stable oil followed by oils containing 100 ppm TBHQ and 1, 5, 10, and 2% PKFO. No significant difference between samples of olive oil containing 100 ppm TBHQ and 1% PKFO was observed. Thus, it was concluded that PKFO at levels lower than 1% could provide stronger antioxidation activity in comparison with TBHQ (the strongest syntactic antioxidant used in the food industry). Moreover, reduction in tocopherol compounds during thermal processing was higher in olive oil containing TBHQ as compared to those in pure olive oil.  相似文献   
105.
The objective of this research was development of a quantitative model of simultaneous contrast (induction) to aid selection of sets of easily identified map colors. The model is an extension of R. W. G. Hunt's model of color appearance. Contrasts between central and proximal colors were used to adjust Hunt's lightness, relative redness-greenness, and relative yellowness-blueness measures. Human subject responses to CRT displays in an experiment were analyzed to produce a set of rules for selecting map colors. Rather than predict average perceptions for central/proximal color combinations, acknowledgment was made of the inherent variability in map readers' perceptions of color by developing generalized perception buffers that accounted for at least 90% of test subject responses. The task of selecting colors that will not be confused once they appear with numerous proximal colors on a map thus becomes a task of selecting colors that do not have buffers that overlap in color space. © 1996 John Wiley & Sons, Inc.  相似文献   
106.
ABSTRACT: Effects of pH, muscle, and storage time on the ability of vacuum-packaged pork chops to bloom were investigated. Low pH samples exhibited more change in color measures during the 30 min blooming period than did the medium and high pH samples. The low pH sample bloomed more rapidly and to a greater extent than medium and high pH samples. Among the 3 muscles, Longissimus had the highest, while Semimembranosus had the lowest a* value and hue angle changes. Overall, refrigerated storage of vacuum packaged pork for 7 d or more resulted in more efficient blooming when pH was low. The ability of vacuum-packaged pork to rebloom is necessary for the meat to regain the consumer-expected pink-red color after opening the vacuum bag.  相似文献   
107.
108.
ABSTRACT:  Beef complexus (chuck), serratus ventralis (chuck), vastus lateralis (round), vatsus medialis (round), and longissimus dorsi (loin) muscles were enhanced (0.3% salt, 0.4% phosphate), vacuum packaged, and aged for 7 or 14 d. Enhancement increased positive sensory attributes (tenderness, juiciness, beef flavor, saltiness) and decreased negative attributes (off-flavors) of all muscles but had greater effects on some than on others. It increased the oily mouthfeel (10%) and saltiness (40%) and decreased the L * value and chroma of the complexus (chuck). It increased tenderness, juiciness, and beef flavor and decreased off-flavors, visual red and brown colors, shear value, and cook loss of the serratus ventrali (chuck) , vastus lateralis (round), vastus medialis (round), and longissiumus dorsi (loin). Aging slightly decreased rancid and liver off-flavor scores, visual brown color, and shear value and increased the hue angle and L * and b * values.  相似文献   
109.
A linear optimal control design for machine excitation is developed to improve the local system stability in a large-scale power system. Dynamic equivalents for the external system are used to provide the controller with information about the original external system. The paper investigates whether external system information helps the controller to stabilize the local system and whether the dynamic equivalents are a reliable source of that information. The validity and accuracy of the proposed method is demonstrated by simulated tests on two sample power systems.  相似文献   
110.
The case for technology in developing regions   总被引:1,自引:0,他引:1  
Alongside good governance, technology is considered among the greatest enablers for improved quality of life. However, the majority of its benefits have been concentrated in industrialized nations and therefore limited to a fraction of the world's population. We believe that technology has a large role to play in developing regions, that "First World" technology to date has been a poor fit in these areas, and that there is thus a need for technology research for developing regions. Despite the relative infancy of technology studies in developing regions, anecdotal evidence suggests that access to technology has a beneficial economic impact. Cellular telephony is probably the most visible application, but there are many others, some of which we cover in this article. The World Bank's infoDev site catalogs hundreds of information and communications technologies (ICT) projects, albeit not all successful. Most of these projects use existing off-the-shelf technology designed for the industrialized world. Although it is clear that there are large differences in assumptions related to cost, power, and usage, there has been little work on how technology needs in developing regions differ from those of industrialized nations. We argue that Western market forces continue to meet the needs of developing regions accidentally at best.  相似文献   
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