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981.
982.
This poem summarizes the fit‐first method of camera evaluation described in Jim Worthey's “Applications of vectorial color.” The algorithm works with the locus of unit monochromats (LUM) in camera and CIE color‐matching spaces. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011;  相似文献   
983.
Estimating average throughput and packet transmission delay for worst case scenario (cell edge users) is crucial for LTE cell planners in order to preserve strict QoS for delay sensitive applications. Cell planning techniques emphasize mostly on cell range (coverage) and throughput predictions but not on delay. Cell edge users mostly suffer from throughput reduction due to bad coverage and consequently unexpected uplink transmission delays. To estimate cell edge throughput a common practice on international literature is the use of simulation results. However simulations are never accurate since MAC scheduler is a vendor specific software implementation and not 3GPP explicitly specified. This paper skips simulations and proposes an IP transmission delay and average throughput analytical estimation using mathematical modeling based on probability delay analysis, thus offering to cell planners a useful tool for analytical estimation of uplink average IP transmission.  相似文献   
984.
Abstract:

Researchers say that teachers can implement an educational innovation without adhering to the principles underpinning its design. Such principles may not adequately take typical classroom conditions into account. The goal of this study was to explore tensions between attempts to implement the principles underpinning knowledge building and the influence of contextual factors that compete for the teacher's attention. To this end, we discuss five excerpts from a discussion of the motion of spinning tops held by a class of Grade‐4 students, coming at the end of a five‐month implementation of knowledge building. Each excerpt is followed first by the teacher's perspective and then by the researcher's perspective. Our analysis highlights two tensions that constrain agency, arising from the students’ need for social development and their need to learn scientific concepts. We offer some suggestions for addressing these tensions.  相似文献   
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A wide variety of motivations for engaging with narratives have been proposed and studied. We propose that underlying these motivations is another, more fundamental motivation. Our premise is that maintenance, defense, and regulation of the personal and social self in daily life are demanding both emotionally and cognitively. Moreover, any individual self is constrained by capability, situation, and social role. Stories and identification with story characters provide a means individuals may use for temporary relief from the task of self‐regulation and from the limitations of individual personal and social identities. Existing supportive research is acknowledged and implications explored, concerning contexts in which story involvement will be particularly attractive and possible impacts on attitudes and acceptance of out‐groups including stigmatized others.  相似文献   
989.
Hydrogenation of p‐nitrophenol (PNP) to p‐aminophenol (PAP) using NaBH4 as a reducing agent was studied as a test reaction for determining the catalytic activity of supported Pt catalysts. The initial reaction rate, which is accessible within less than 10 min via online UV‐vis spectroscopy at room temperature, ambient pressure, and in water as solvent, was applied as measure for catalytic activity. For three Pt catalysts supported on porous SiO2, porous glass, and Al2O3, respectively, significant differences in the catalytic activity by almost one order of magnitude were observed. However, especially in the case of very active catalysts, limitations of the reaction by internal or external mass transfer have to be considered.  相似文献   
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