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21.
刘自毫 《艺术与设计.数码设计》2007,(3)
本文以《烟草控制框架公约》在我国正式生效后,按照《公约》对卷烟包装的规定,我国的卷烟商标和包装在很大程度上要重新设计和制作为着眼点,从正确履行《烟草控制框架公约》保持中式卷烟包装设计特色、正确理解中式卷烟内涵,明确烟标和包装设计方向、中式卷烟包装和色彩与消费心理有着密切的关系以及中式卷烟包装应该提高环保意识、减少环境污染和中式卷烟包装应提高技术含量,利用核心技术进行防伪设计等方面,论述了中式卷烟包装设计的发展方向及注意的事项。 相似文献
22.
Anatoli VrocharidouAuthor Vitae Ilias Efthymiou Author Vitae 《Computers & Education》2012,58(1):609-616
The present study approaches the Internet as a social space, where university students make use of computer mediated communication (CMC) applications, i.e. e-mail, instant messaging and social network sites, in order to satisfy social and academic needs. We focus on university students, because they represent one of the most avid groups of CMC users and additionally, because they are expected to carry their perceptions of media with them into the work place and their social life. In order to investigate this issue, we conducted an empirical research using, as a target group, a sample of students from a specific Greek University. Grounded in the “uses and gratifications” perspective, we investigated the various profiles of CMC use by students along with (a) the students’ perceptions about social and academic usefulness of CMC applications, (b) the extent up to which these perceptions are correlated with students’ prior experience with the use of CMC applications, and (c) how both of these factors can predict the frequency of present use of CMC for social or academic purposes respectively. The results reveal that although these three CMC applications constitute “functional alternatives” (media that satisfy similar needs) they are different to the degree of their “functionality” for the gratification of social and academic needs. Furthermore, the degree of CMC use by students is not correlated with the years of CMC experience, but with the profile of use that students dynamically adopt according to their daily needs and preferences. The results provide evidence for the current CMC use by university students and can be useful for the implementation of further academic policies regarding CMC use in Higher Education settings. 相似文献
23.
《国际计算机数学杂志》2012,89(1):21-40
We consider the multiprocessor scheduling of unit time tasks with precedence constraints and finite set of limited resources. Each task demands some amount of resources for its execution and the total demand for each kind of resources must not exceed a certain limit at any instant of time. Our objective is to find out the minimum time schedule which satisfies the partial orders and the resource usage constraints. We have applied Genetic Algorithm for the present problem. We have shown that the Genetic Algorithm is quite superior to the First Fit Decreasing method. 相似文献
24.
25.
基于智能工程的思想,提出了一种并行分层结构的集成化智能CAD系统,并在钟表CAD中得到成功应用,同时还首次将布局理论应用到钟表机芯设计中。 相似文献
26.
Weilin Xu Jun Deng Jingxue Qu Shanjun Liu Wei Wang 《Canadian Metallurgical Quarterly》2004,130(2):160-164
A series of experiments was conducted to investigate the influence of aeration on plane jet scour. The scour holes caused by the aerated and the nonaerated jets were compared under the same conditions of jet velocity, water discharge per unit width, and tailwater depth. A quantitative relationship between the air concentration of jet and the relative scour depth was established, which is not affected by jet velocity and water discharge per unit width. The profile of the scour hole was found to mainly depend on the scour depth under the same conditions of bed material and tailwater depth and affected very little by the air concentration itself in the test range. The aeration influences the shape of the scour hole mainly through decreasing the scour depth. The scour holes formed under aerated and nonaerated conditions are self-similar. 相似文献
27.
Two triphenylamine-substituted benzimidazole derivatives were synthesized for use as efficient deep-blue emitters in nondoped fluorescent organic light-emitting diodes (FLOLEDs). The molecular design of 4′,4′′-(1H-benzo[d]imidazole-1,2-diyl)bis(N,N-diphenylbiphenyl-4-amine) (T2B) to limit the molecular packing density enabled T2B-based devices to suppress the exciton quenching by a bulky three-dimensional structure. Nondoped FLOLEDs fabricated using T2B as a blue emitter exhibited an external quantum efficiency of 4.67% with color coordinates of (0.15, 0.08). 相似文献
28.
Investigation into the synergistic effects in ternary cementitious systems containing portland cement, fly ash and silica fume 总被引:1,自引:0,他引:1
This research was primarily conducted to verify the presence of synergistic effects in ternary cementitious systems containing portland cement (OPC), class C fly ash (FA) and silica fume (SF). A subsequent objective of the study was to quantify the magnitude of the synergy and to determine its source. For a ternary mixture containing 20% FA and 5% SF by mass, the synergistic effect was observed mostly at later ages (7 days onward) and it resulted in an increased compressive strength and resistance to chloride ion penetration as well as a reduced rate of water absorption (sorptivity) compared to predictions based on individual effects of FA and SF in respective binary systems. The observed synergy was attributed to both chemical and physical effects. The chemical effect manifested itself in the form of an increased amount of hydration products. The physical effect associated with packing density was, somewhat contrary to general belief, not due to an optimized particle size distribution of the binder components of the ternary cementitious system. Instead, it was the result of smaller initial inter-particle spacing caused by lower specific gravities of both FA and SF which, in turn, led to a lower volumetric w/cm. If the mixture design was adjusted to account for these differences, the physical effect would be diminished. 相似文献
29.
薄壁塑件的应用主要是节约材料,其模具设计与通常成型模具有着不同要求.包装盒壁厚仅有1.0mm,就盒底模具设计中结构设计、浇注、冷却、排气和脱模等部分进行了分析,并将设计方案作了详细的阐述.模具经过实践证明:结构合理,产品无变形等缺陷,受到用户的认同. 相似文献
30.
Maximilian Pleines Werner Kunz Thomas Zemb 《Journal of surfactants and detergents》2019,22(5):1011-1021
In this work, we show by which mechanism branching of the hydrocarbon chains influences the cloud point of nonionic, ethoxylated surfactants. The temperature-induced separation into a dilute and a concentrated liquid phase is of liquid–gas type and can be explained by the relative probability of endcaps and branching points of the cylindrical micelles in both phases. The influence of branches on the hydrocarbon chains can be easily understood by means of spontaneous and effective packing concepts, while quantification via hydrophilic/lipophilic balance (HLB), hydrophilic-lipophilic difference (HLD), and HLD-Net Average Curvature requires parametrization. The phase equilibrium above the cloud point phenomenon is equivalent to the Winsor I type phase equilibrium, one of the five known phase equilibria in ternary systems. 相似文献