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81.
Five experiments addressed the role of color grouping in preview search (D. G. Watson & G. W. Humphreys, 1997). Experiment 1 used opposite color ratios of distractors in preview and second search displays, creating equal numbers of distractors in each color group in the final display. There was selective slowing for new targets carrying the majority color of the old items. This effect held when there was no bias in the preview and only the second search set had an uneven color ratio (Experiment 2). In Experiment 3, participants had foreknowledge of the target color, and effects were shown over and above those due to color biases. Experiment 4 demonstrated negative color carryover even when previews changed color. Experiment 5 showed reduced color carryover effects when previews were presented more briefly. Collectively, the results provide evidence for inhibitory carryover effects in preview search based on feature grouping. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
It has been reported that it is harder to switch to a strong, well-practiced task from a weaker, less-practiced task than vice versa. Three experiments replicated this surprising asymmetry and investigated how it is affected by a reduction in interference between tasks. Experiment 1 progressively delayed the onset of the stimulus attribute associated with the stronger task. Experiments 2 and 3 separated the response sets of the tasks. Both manipulations reduced, without eliminating, interference of the stronger with the weaker task but reversed the asymmetry of switch costs, resulting in a larger cost of switching to the weaker task. The results are interpreted in terms of a model of the interactions between control input, task strength, and task priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
ABSTRACT: How the quality of cold-smoked Atlantic salmon ( Salmo salar ) is affected by freezing the raw fish as whole fish, as gutted fish, and as fillets before smoking, and by freezing the finished product after smoking was studied. Freezing before smoking resulted in increased product yield and water content, but softer texture and increased K-value. Freezing reduced the content of astaxanthin but increased the lightness and the color intensity of the flesh. Gaping increased when the fish was frozen as fillets before smoking. Freezing only after smoking led to fewer changes in quality than freezing before smoking, whereas refreezing the finished products had little additional effect on quality.  相似文献   
84.
在工业CT断层图像缺陷检测应用中,提出了将数字高程模型DEM与伪彩色技术一起应用于二维灰度图像缺陷检测领域的算法流程。应用该算法流程,能够充分利用CT断层灰度图像信息,获得清晰的视觉检查效果,从而大大增强了系统检测缺陷的能力。在大型工业CT图像重建与检查分系统中采用该算法流程已经取得了较为理想的效果。  相似文献   
85.
减少GPS接收机多径干扰的办法是采用特殊天线和在接收机中采取一定的措施。文中针对窄相关技术展开分析。重点分析影响接收机多径误差的因素及窄相关的性能,并给出仿真及分析结果。  相似文献   
86.
Image sources, such as digital camera captures and photographic negatives, typically have more information than can be reproduced on a photographic print or a video display. The information that is lost during the tone/color rendering process relates to both the extended dynamic range and color gamut of the original scene. In conventional photographic systems, most of this additional information is archived on the photographic negative and can be accessed by adjusting the way the negative is printed. However, most digital imaging systems have traditionally archived only a rendered video RGB image. As a result, it is not possible to make the same sorts of image manipulations that historically have been possible with conventional photographic systems. This suggests that there would be an advantage to storing images using an extended dynamic range/color gamut color encoding. However, because of file compatibility issues, digital imaging systems that store images using color encoding other than a standard video RGB representation (e.g., sRGB) would be significantly disadvantaged in the marketplace. In this article, we describe a solution that has been developed to maintain compatibility with existing file formats and software applications, while simultaneously retaining the extended dynamic range and color gamut information associated with the original scenes. With this approach, the input raw digital camera image or film scan is first transformed to the scene‐referred ERIMM RGB color encoding. Next, a rendered sRGB image is formed in the usual way and stored in a conventional image file (e.g., a standard JPEG file). A residual image representing the difference between the original extended dynamic range image and the final rendered image is formed and stored in the image file using proprietary metadata tags. This provides a mechanism for archiving the extended dynamic range/color gamut information, which is normally discarded during the rendering process, without sacrificing interoperability. Appropriately enabled applications can decode the residual image metadata and use it to reconstruct the ERIMM RGB image, whereas applications that are not aware of the metadata will ignore it and only have access to the sRGB image. The residual image is formed such that it will have negligible pixel values for those portions of the image that lie within the sRGB gamut, and will therefore be highly compressible. Tests on a population of 950 real customer images have demonstrated that the extended dynamic range scene information can be stored with an average file size overhead of about 8% compared to the sRGB images alone. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 251–266, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10160  相似文献   
87.
先用硅胶对大连石化分公司3号喷气燃料馏分油中的有色组分进行吸附,然后分别用二氯甲烷和甲醇两种脱附剂对已吸附有色组分的硅胶进行脱附,得到两种含有色组分的两种溶液.应用红外光谱和色-质联用分析法对富集的有色组分进行了分析鉴定.分析了不同时期喷气燃料馏分油的性质及其对颗粒白土吸附脱色性能的影响.结果表明,大连石化分公司3号喷气燃料馏分油中的有色组分主要成分为C8~C14醇类、酮类、苯酚、甲酚和多烷基酚类及一些多聚体化合物.脱硫醇塔前进料馏分油的性质差异很小,而脱硫醇塔后馏分油的性质变化很大,颜色显著加深.脱硫醇塔操作末期温度高而引起喷气燃料馏分中不稳定组分的氧化转化导致颜色变深.颗粒白土脱色处理赛氏色值高的喷气燃料馏分油明显比处理赛氏色值低的喷气燃料馏分油的效果要好.脱硫醇塔操作不当造成油品恶化是导致颗粒白土吸附脱色失活很快的主要原因.控制脱硫醇塔乃至蒸馏系统操作条件(特别是温度),对延长颗粒白土的使用时间至关重要.  相似文献   
88.
The present article reports the investigation of the effects of surrounding brightness on a visual search for three safety colors: red, orange, and yellow. Images of visual stimuli consisting of an array of colored circles placed on a large visual field (a visual angle of 40°) were displayed on an 80‐in. screen with a DLP projector. Experiment I examined the search efficiency under three levels of background luminance that were equivalent to the three target luminances. The results showed that the search efficiency for the orange target decreased as the number of distractors increased, under each of the background luminance levels, whereas the efficiency scarcely decreased for the red and yellow targets. Although a reduction in background luminance increased the search efficiency for the orange target, it is suggested that the effect of background luminance is smaller than the effect of the target color in search efficiency. Experiment II examined the search efficiency under three conditions of low levels of incident illuminance, which were matched with a linear regression to the luminance of color chips of safety colors measured twilight conditions. The results showed that the search efficiency for the orange target decreased as the number of distractors increased under each of the different illuminance conditions, whereas the efficiency scarcely decreased for red and yellow targets. Furthermore, as illuminance decreased, the search time for the orange target was more greatly impacted than for red or yellow. These results imply that the recognition of orange tends to be influenced by the surrounding brightness. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 400–409, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20152  相似文献   
89.
星间激光通信技术进展与趋势   总被引:3,自引:3,他引:0  
较详细地评述了目前国外卫星间光通信技术研究的现状.根据关键单元技术的进展情况,总结了未来星间光通信系统的发展趋势。  相似文献   
90.
Parity space approach and H2 approach are two important fault detection approaches. This paper studies the relationship between these two approaches, which reveals frequency domain characteristics of the optimal solution of the parity space approach on the one side and provides a numerical solution of the H2-optimal design of residual generators on the other side.  相似文献   
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