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71.
The effect of unit k/s calculation and spectral overlapping on the performance of color matching
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There are several approaches to dyeing recipe formulation in the textile industry, because the accuracy of computer recipe prediction is not very high. There are several theories such as colorimetric and spectrophotometeric appraches on color reception. This work addressed the effect of the calibration method as the calculation of unit k/s and spectral overlapping of the components of the mixture on the accuracy of recipe prediction in dyeing nylon with acid dye. To this aim, the unit k/s was calculated using single and binary mixture samples. Two types unit k/s were used for the recipe prediction of ternary mixture dyed samples with low and high overlapping reflectance spectra. The obtained results indicated that the unit k/s of single component differed from the unit k/s of bicomponent mixture. The accuracy of recipe prediction using unit k/s of single component was less than that of the binary mixture. However, the performance of the recipe prediction of high level overlapping was found to be more than that of the low level overlapping mixture. Subsequently, the accuracy of color matching depended on the reflectance spectra similarity (spectral overlapping) of the components of the mixture. 相似文献
72.
对新型冠状病毒肺炎综述文献进行网络结构分析可为新冠疫情的应对提供有效的理论支持。采用可视化软件CiteSpace对Web of Science数据库中新型冠状病毒肺炎综述文献的引文数据进行共被引网络分析,经统计发现文献共被引网络的度分布呈幂律分布,网络连通性较强且存在小世界现象。运用团渗流算法对其进行重叠社团挖掘,检测到7篇同时跨3个社团的核心文献,结合被引频次对网络重叠节点的功能进行验证。借助网络重叠节点的ID符号、介数中心性指标发现相应研究主题间联系紧密。通过不同特征的重要网络节点,能够有效挖掘到相关的研究主题。 相似文献
73.
74.
Pauker Kristin; Weisbuch Max; Ambady Nalini; Sommers Samuel R.; Adams Reginald B. Jr.; Ivcevic Zorana 《Canadian Metallurgical Quarterly》2009,96(4):795
Exponential increases in multiracial identities, expected over the next century, create a conundrum for perceivers accustomed to classifying people as their own- or other-race. The current research examines how perceivers resolve this dilemma with regard to the own-race bias. The authors hypothesized that perceivers are not motivated to include ambiguous-race individuals in the in-group and therefore have some difficulty remembering these individuals. Both racially ambiguous and other-race faces were misremembered more often than own-race faces (Study 1), though memory for ambiguous faces was improved among perceivers motivated to include biracial individuals in the in-group (Study 2). Racial labels assigned to racially ambiguous faces determined memory for these faces, suggesting that uncertainty provides the motivational context for discounting ambiguous faces in memory (Study 3). Finally, an inclusion motivation fostered cognitive associations between racially ambiguous faces and the in-group. Moreover, the extent to which perceivers associated racially ambiguous faces with the in-group predicted memory for ambiguous faces and accounted for the impact of motivation on memory (Study 4). Thus, memory for biracial individuals seems to involve a flexible person construal process shaped by motivational factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Existing models of causal induction primarily rely on the contingency between the presence and the absence of a causal candidate and an effect. Yet, classification of observations into these four types of covariation data may not be straightforward because (a) most causal candidates, in real life, are continuous with ambiguous, intermediate values and because (b) effects may unfold after some temporal lag, providing ambiguous contingency information. Although past studies suggested various reasons why ambiguous information may not be used during causal induction, the authors examined whether learners spontaneously use ambiguous information through a process called causal assimilation. In particular, the authors examined whether learners willingly place ambiguous observations into one of the categories relevant to the causal hypothesis, in accordance with their current causal beliefs. In Experiment 1, people's frequency estimates of contingency data reflected that information ambiguous along a continuous quantity dimension was spontaneously categorized and assimilated in a causal induction task. This assimilation process was moderated by the strength of the upheld causal hypothesis (Experiment 2), could alter the overall perception of a causal relationship (Experiment 3), and could occur over temporal sequences (Experiment 4). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Comments by on an article entitled "Racial microaggression? How do you know?" by Rafael S. Harris Jr. (see record2008-05553-011). The author states that in our original article we asserted that the racial reality of POC was generally different from the racial reality of White Americans and that often times interpretations of situations and events are the result of worldviews or racial identity. When references are made to POC, or to “visible racial/ethnic groups,” reference is being made not only to the shared cultural characteristics, norms, values, and attitudes of the group (African American, Asian American, American Indian, and Latino/Hispanic American) but to a self-designation of racial identity formed from sociopolitical experiences of unequal social, economic, legal, and political power in U.S. society that are based on visible racial characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
针对沃森-瓦特测向处理中幅相不一致对定单向及测向准确度的影响问题,分析了定单向法则失效的原因,提出了针对参考通道输出信号的全相位校正方法.利用该方法获取的最优相位修正量对参考通道输出信号进行移相处理,使测向通道与参考通道输出信号之间的相位关系满足定单向法则的要求,提高了定单向方法的稳健性.通过对测向误差特性的分析,给出了因测向通道间幅相误差导致的测向误差表达式,提出了利用最小二乘法计算误差曲线的拟合参数,从而可实现利用有限区域内的测向误差测量数据对全方位测向误差的估计,提高测向的准确度.通过仿真验证了提出方法的有效性. 相似文献
78.
本文介绍了河海大学第一栋文科实验楼的创作理念,阐述了如何运用体块的扭转、重叠、交织、穿插,从而解决复合功能的问题。方案通过以上手法,形成活跃的建筑形象,为严谨的工科学校带来浪漫的节奏,突出了理性与浪漫交织这一构思。 相似文献
79.
富水地层中重叠隧道施工引起土体变形研究 总被引:2,自引:0,他引:2
重叠隧道施工易产生隧道结构不稳定和地层变形等问题。重叠隧道富水地层施工时,土层开挖应力释放和地下水渗流共同作用使得地层和隧道变形问题显得更加突出,增加了施工难度。以深圳地铁5号线重叠隧道为背景,采用数值方法研究了开挖应力释放和渗流作用在重叠隧道施工不同阶段对隧道结构和土层变形的影响,得到富水地层重叠隧道施工土层变形规律,同时提出了控制地层变形措施。重叠隧道下洞施工时,采用设置超前注浆支护能有效控制开挖应力释放引起拱顶沉降,开挖完成后隧道拱顶在渗流作用下沉降稳定,而隧道上覆土层因失水固结产生较大工后沉降,同时地表沉降槽深度和半径在渗流作用下不断增大;为避免下洞隧道在渗流作用引起上洞隧道整体沉降,上洞在下洞施工引起土体变形稳定后进行施工。上洞开挖应力释放引起较大地层沉降,开挖应力释放引起较大地层沉降,渗流因素引起地层工后变形较小,地表沉降槽深度迅速增大而影响半径保持稳定。 相似文献
80.
目的 设计超高速线光斑激光熔覆送粉喷嘴,在极高的熔覆效率和极低的搭接率下制备不锈钢熔覆涂层,对比研究圆光斑及线光斑下的熔覆涂层的微观组织结构及性能。方法 基于送粉喷嘴流场及粉末粒子运动轨迹的模拟研究,设计超高速线光斑激光熔覆专用送粉喷嘴。在此基础上,以27SiMn为基体,采用1 mm´ 10 mm线光斑,在10%搭接率、熔覆效率4.5 m2/h下,采用超高速线光斑激光熔覆FeCr合金薄涂层;作为对比,采用超高速圆形光斑(2 mm)激光在0.2 m2/h熔覆效率下熔覆FeCr合金涂层。采用SEM、XRD对比分析线光斑/圆光斑涂层微观组织结构与涂层显微硬度。结果 通收束角度为25°~27°的单流道送粉喷嘴可得到分布均匀、飞行速度适中的粉末束流。对比研究超高速线光斑及圆光斑激光熔覆涂层可知,相同扫描速度下2种光斑制备的涂层均较为致密,无裂纹与气孔,由熔覆层底部到熔覆层表面均呈现出平面晶—柱状晶—等轴晶的变化趋势,线光斑和圆光斑涂层硬度在700~800HV,线光斑下的熔覆层硬度分布更加均匀,表面粗糙度Ra可低至<4 μm,搭接率可低至10%,熔覆效率可达 4.5 m2/h,远高于圆光斑激光下的熔覆效率。结论 2种光斑模式下的涂层微观组织、相组成及硬度相当,但超高速线光斑激光熔覆层表面光洁度更高,表面粗糙度更低,熔覆效率可达圆光斑的20倍。 相似文献