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831.
包装装潢中的图形创意 总被引:2,自引:2,他引:0
图形创意在商品包装装潢设计中起着重要的作用,图形的传统和现代的构成形式使产品更具风格,独创性是其生命力所在,而联想和想象又是创造力的主要源泉,这种联想和想象力通过自然形、抽象形和寓意图形来体现.所以包装设计需要突破,通过图形创意的不断完善,促销产品,使其为市场接受,被顾客赞誉. 相似文献
832.
《Advances in Engineering Software》2007,38(10):649-656
An immune optimization algorithm is proposed in this paper based on the immune negative selection. The algorithm NSIOA is motivated by the negative selection mechanism in biological immune recognition. Different from the existing immune optimization methods, NSIOA constantly removes the worst solutions to get the optimal solution. Considering that removal of poor members of a population might lead to the loss of design information that may actually help identify better solutions in the search space, the proposed NSIOA is designed to keep the diversity of antibodies while removing poor members, therefore the algorithm will converge to global optimal solution with high probability. The convergence property and the complexity of the algorithm have also been analyzed. To illustrate the efficiency of the algorithm is used in solving the travel salesman problem. The theoretical analysis and experimental results show that the algorithm is of a strong potential in solving practical problems. 相似文献
833.
《Environmental Modelling & Software》2007,22(10):1488-1497
A Laplace transform representation is used to describe the changes in atmospheric CO2 in response to emissions. The formalism gives an explicit representation of generic relations that are less clear when model results are presented as numerical integrations with particular parameter values. In particular, the Laplace transform formalism clarifies some issues involved in inversion of ice-core data and analysis of geosequestration. The airborne fraction is expressed as the emission growth rate multiplied by the Laplace transform of the atmospheric response function, evaluated at the growth rate. This representation emphasises that historical data only capture carbon cycle dynamics over a limited range of time-scales. The Laplace transform formalism provides a basis for expressing uncertainties in the response function in terms of the Padé–Laplace transformation used for fitting sums of exponentials. 相似文献
834.
《Materials Letters》2007,61(4-5):1134-1136
In the present study, vapor-grown carbon nanofibers with 0.5 wt.% loading were dry-mixed with polypropylene powder by mechanical means, and extruded into filaments by using a single screw extruder. TGA results showed that decomposition temperature has increased 18.9 °C by filling CNFs in polypropylene. Tensile results demonstrated that tensile modulus and tensile strength have increased by 154% and 69.5%, respectively. A SEM picture indicated that an increase in mechanical properties is due to the well dispersion and alignment of CNFs in the filaments. 相似文献
835.
Wei Fen Zhang Xi Guang Chen Pi Wu Li Cheng Sheng Liu Qiang Zhi He 《Drying Technology》2008,26(1):108-115
Three kinds of carboxymethyl chitosan/β-cyclodextrin microspheres loaded with theophylline were prepared by spray drying intended for pulmonary delivery. Mucociliotoxicity, permeation rate, and drug release characteristics of the product were investigated. The microspheres obtained by spray drying were found to be spherical with smooth or wrinkled surfaces. The mean particle size was between 3.39 and 6.06 µm. The microspheres demonstrated high product yield (43.7-50.2%), high drug loading (13.7-38.1%), and high encapsulation efficiency (86.9-92.8%). FT-IR indicated that there were interactions of theophylline with carboxymethyl chitosan matrix. Further studies on mucociliotoxicity and permeation confirmed that microspheres had better adaptability and high permeation rate. In vitro drug release from the microspheres was not related to the drug/polymer ratios. 相似文献
836.
Flammability ranking of foliage species by factor analysis of physical and chemical pyric properties
In this paper, factor analysis is introduced to evaluate the flammability of 55 foliage species that may be used in China for construction of the fuel break network of forest strips with lower flammability. Six pyric parameters, i.e. air dry moisture content, absolute dry moisture content, ignition point, ash content, caloric value and extractive content, are measured and used as variables for factor analysis. The covariance analysis shows that four principal factors can be extracted to reflect the flammability in different physical and chemical senses. In terms of the contributions of the four factors to the variances and the physical significance of the relevant parameters, the four factors are, respectively, termed as ‘flaming factor,’ ‘air dry factor,’ ‘ash factor’ and ‘absolute dry factor.’ The stability of the factor analysis method is examined by a different number of samples considered, and the variation degrees of the orderings indicate that the method has high reliability to measure the total flammability of foliage species. The results of the flammability evaluation are verified by comparison with the recommended tree species in the Chinese technology standard. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
837.
Keiji Itabashi Takuji Ikeda Akihiko Matsumoto Kunikazu Kamioka Masanao Kato Kazuo Tsutsumi 《Microporous and mesoporous materials》2008,114(1-3):495-506
Four types of Rb-aluminosilicate zeolites were hydrothermally synthesized in pure phase for the first time from Rb-aluminosilicate gels without using any organic structure-directing agent (SDA) under stirring conditions. The crystal structure of each zeolite was refined by Rietveld analysis of the X-ray diffraction (XRD) data. These crystal structures were confirmed to be Rb-mordenite, Rb-merlinoite, a new aluminosilicate zeolite with an ATT framework topology, and Rb-offretite denoted by RMA-1, RMA-2, RMA-3, and RMA-4, respectively. The Si/Al ratio of RMA-1 with an MOR topology varied from 5.3 to 8.0; however, the variation of the Si/Al ratios of the other zeolites was rather small. The crystal system of RMA-2 was tetragonal with space group I4/mmm, where two Rb sites were distributed at the center of an 8-membered ring (MR). On the other hand, two Rb sites in RMA-3 were located at the center of the 8-MR in small two cages. The structure of RMA-4 was identified as the OFF type with a local disorder or defect, which included a small amount of an intergrown ERI phase. 相似文献
838.
839.
《Food Control》2006,17(10):781-788
A Brazilian produce plant was evaluated according to good agricultural practices (GAPs) using a checklist. The agricultural water was sampled for total and faecal coliform and Escherichia coli counts. Equipment/handler sanitary facilities, the handling of agrochemicals and pesticides, records of the composting process, prior analysis of the irrigation water for the identification of heavy metals and pesticide residues, inadequate temperature control of the raw material storage room, qualified person to manage the operations and periodic training programmes on food manipulation, hygiene and microbiology, were the main critical points found during the inspection. Microbiological analyses of the irrigation water gave counts between 0.3 and 1.2 log MPN/ml for total and faecal coliforms, respectively and absence of E. coli. The results are discussed and the necessary corrections suggested in order to improve process safety. 相似文献
840.