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随着数码相机提供的原稿增多和彩色喷墨印刷的普及,一种不同于4色制版彩印的多色印刷技术进入了实用市场领域。具体地讲,它将原稿分解为6色或7色以上。多色印刷是以四色制版印刷的CMYK数据为基础,实现了宽广的色调范围,即色域比CMYK更大,可以把原稿上细微层次都复制出来,因此有较好的发展前景。六色印刷最早是美国Pantone公司开发的,它采用独特的6色油墨进行印刷,即使用青、品红、黄、黑、橙、绿色墨,除了黑、蓝以外,其他色墨中含有荧光颜料,具有非常鲜明的色彩。该6色油墨不是在常规的四色油墨外加进橙和绿,而是由Pantone公司认同的6种油墨构成指定的一组,由油墨制造厂家单独生产。 相似文献
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基于UV喷墨的彩色3D打印研究 总被引:1,自引:1,他引:0
目的研究以UV喷墨为成型材料的彩色3D打印方案。方法以纸张为承印介质,采用UV喷墨打印方式,在5张同种纸张表面打印不同墨层数的黄、品、青、黑和白等5种颜色的色块和IT8.7-3CMYK i1 PM 5.0.5标版,对比分析不同墨层数色块的厚度和颜色再现情况,以及白色油墨对色域的影响。结果对黄、品、青、黑、白等5种油墨来讲,第1层油墨会与纸张表面发生较强的渗透和铺展作用,影响高程精度;随着墨层数增加,黄、品和青等3种色油墨的亮度逐渐下降,色相逐渐偏离;在纸张表面均匀打印1层白色实地油墨,可改善纸张偏色情况,且白色油墨具有较好的色彩再现性。结论能够以多层白色油墨的叠加实现3D模型的高度,以若干层彩色油墨打印实现3D模型的色彩方案,从而实现UV喷墨彩色3D打印。 相似文献
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基于空间区域分割的四面体网格剖分色域描述算法 总被引:3,自引:1,他引:2
目的提出一种新的数字输出设备色域边界描述算法模型,以实现数字输出设备色域的三维立体准确再现和色域体积的精确求取。方法通过空间区域分割算法确定Epson Stylus Pro 7910打印机呈色范围的最佳颜色空间分区,利用四面体网格剖分技术对各分区色域边界进行描述,同时从色域体积、边界点再现精度等方面,对该方法和基于改进凸壳算法下的设备色域匹配适性进行对比分析。结果该色域边界描述新算法模型在描述的准确性和再现精度方面,明显优于改进后的凸壳算法。结论该算法下各边界颜色点再现精度平均ΔE和最大ΔE均在2以内,并且设备色域体积明显大于改进凸壳算法下的设备色域体积。 相似文献
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目的为了提升水印抗打印扫描攻击的鲁棒性,提出一种窄色域抗打印扫描全息水印算法。方法制作打印机的ICC特性文件,应用特性文件转换宿主图像到CMYK颜色模式,从而获得适应该设备的窄色域,将制成全息图的水印嵌入到宿主图像的DWT域内。结果实验表明,该算法经历打印扫描后可顺利提取水印,且打印扫描后获得的水印图像保真度较高。与在RGB颜色模式中嵌入水印相比,该算法水印的鲁棒性和宿主图像的保真度均具有明显优势;相较于嵌入水印到默认转换的CMYK颜色模式,鲁棒性相当,该算法宿主图像的保真度具有明显优势。结论该窄色域算法可提升打印扫描过程中颜色传递的一致性,结合全息图不可撕毁的优势权衡了鲁棒性与保真度的关系,该算法有益于数字水印在防伪印刷领域的应用。 相似文献
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研究了一类时滞分数阶计算机病毒模型Hopf分岔的控制问题。在非受控系统的第一个方程中引入周期脉冲时滞反馈控制器,采用半解析半数值的方法证明了受控系统与其线性化平均系统在一定意义下的等效性,并以此作为理论基础,采用线性化方法和分数阶Laplace变换推导受控系统发生Hopf分岔的临界值,得到系统的稳定域范围以及稳定域随控制器参数的变化情况。结果说明通过调节增益参数值,可有效的延迟系统Hopf分岔的发生。最后,通过恰当的数值模拟验证了理论分析的正确性和可行性,并对比了不同控制增益参数对系统稳定域的影响。 相似文献
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目的研究基于光谱多色分色中颜色分区的判断算法。方法提出一种基于光谱的颜色分区判断算法,该算法引入特征光谱的提取和匹配算法,并在此基础上设计颜色分区判断算法。针对该算法流程中的参数,设计实验进行推算。结果将光谱曲线的值域范围划分为12个等级,目标光谱与分区的距离和目标光谱与所有分区距离最小值的差值小于14%,预测光谱与目标光谱的RRMS小于0.01,色差小于1.5时,能够得到最佳的分区判断结果,每个色块的判断次数为1.93,约为遍历算法的24%。结论提出的基于光谱颜色分区算法能够有效地对目标光谱所在分区进行准确判断,简化基于光谱的多色分色算法流程。 相似文献
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基于点集模型的LabPQR空间光谱色域映射算法 总被引:2,自引:2,他引:0
目的 针对色度色域映射中出现的同色异谱现象, 提出一种基于点集模型的光谱域映射算法。方法 以设备采样样本为基础, 在LabPQR空间内构造色度色域和PQR色域, 以此描述光谱色域; 采用分级映射方法, 在Lab和PQR等2个子空间内对目标光谱依次判断并进行映射。结果 以munsell 1269个色块为检验样本进行试验, 结果显示: 提出算法色度误差为1.0779, 光谱误差为5.12%。结论 提出算法能够有效降低同色异谱现象, 并拥有较高的光谱输出精度, 映射之后的结果能够满足在多种光源下与目标的视觉匹配。 相似文献
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A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils. 相似文献
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The end of over unit products of more than Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits beer wine yellow wine fruit syrup wine others cover over % of the national top-branded liquor products.…… 《中国标准化(英文版)》2008,25(1):30
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.…… 相似文献
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Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster. 相似文献
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N.A. Odintsova N.V. Ageenko K.V. Kiselev N.M. Sanina E.Y. Kostetsky 《International Journal of Refrigeration》2006,29(3):387
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes. 相似文献
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David R. Smith F. R. Fickett 《Journal of research of the National Institute of Standards and Technology》1995,100(2):119-171
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability. 相似文献
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Fco. Javier Franco Pérez Marc Gener Moret 《Materials and Manufacturing Processes》2017,32(7-8):876-884
ABSTRACTThe production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials. 相似文献
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As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion. 相似文献
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Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting. 相似文献
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TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure. 相似文献
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R. Owsiński S. Kamiński M. Szymaniec A. Niesłony T. Łagoda 《Materialwissenschaft und Werkstofftechnik》2015,46(10):1059-1067
The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase. 相似文献