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排序方式: 共有402条查询结果,搜索用时 93 毫秒
1.
Shmuel Borenstain Gil Bar-Haim Keren Goldshtein Gili Cohen-Taguri 《Color research and application》2020,45(6):1153-1169
Investigation of ink formulation options with the purpose to obtain color-gamut-optimal set of Cyan Magenta and Yellow CMY inks is reported. Implementation of the thickness dependent Kubelka-Munk model on multiple ink layers having different and well-defined thicknesses, provides characteristic absorption and scattering (K, S ) spectra of the ink ingredients. These data enable accurate computation of the reflectance spectrum and thus the L*a*b* color coordinates for any given ink thickness or substrate. Pigment materials investigated are quinacridone as magenta, copper-phthalocyanine as cyan, and arylide yellow. Scaling the peak of the absorption band to the number of molecules per unit area for the specific pigments studied in this article provides the molar extinction coefficients, 1.21 × 104 , 4.7 × 104 , and 3.3 × 104 cm2/millimole respectively, regardless of the different ink formulations used, in accord with Avogadro's principle. Having a set of three pairs of K, S spectra is used to compute the color gamut of any CMY color combination in the L*a*b* space as a function of ink layer thickness and formulation. Using an iterative algorithm, a color-gamut-optimal set of CMY inks is obtained. 相似文献
2.
我国海洋石油钻井平台现状与技术发展分析 总被引:7,自引:2,他引:5
海洋油气开发装备产业是直接关系到海洋油气资源开发、影响国家能源稳定和经济安全的战略产业。海洋石油钻井平台是海洋油气开发的关键装备,我国海洋石油装备产业在海洋油气产业持续快速发展的带动下,正处于高速发展的新时期。对我国海洋石油钻井装备产业发展现状及市场需求进行了深入研究,并对海洋石油钻井平台技术特点做了介绍,重点分析了该项技术的发展状况,从钻井平台类型和技术含量等方面指出我国与世界先进海洋石油钻井平台的主要差距,并提出了若干发展建议。 相似文献
3.
Computing clusters (CC) consisting of several connected machines, could provide a high-performance, multiuser, timesharing environment for executing parallel and sequential jobs. In order to achieve good performance in such an environment, it is necessary to assign processes to machines in a manner that ensures efficient allocation of resources among the jobs. The paper presents opportunity cost algorithms for online assignment of jobs to machines in a CC. These algorithms are designed to improve the overall CPU utilization of the cluster and to reduce the I/O and the interprocess communication (IPC) overhead. Our approach is based on known theoretical results on competitive algorithms. The main contribution of the paper is how to adapt this theory into working algorithms that can assign jobs to machines in a manner that guarantees near-optimal utilization of the CPU resource for jobs that perform I/O and IPC operations. The developed algorithms are easy to implement. We tested the algorithms by means of simulations and executions in a real system and show that they outperform existing methods for process allocation that are based on ad hoc heuristics. 相似文献
4.
Recent advances in the realization of individual molecular‐scale devices [1,2] highlight the integration of individual devices into large‐scale functional circuits as the major challenge. DNA‐programmed assembly is a promising avenue in that direction due to the large amount of information that can be coded into the molecules and the ability to translate that information into physical constructs [3]. Large‐scale DNA‐templated electronics require, however, complex manipulation of double‐stranded DNA (dsDNA) molecules, as well as patterning of the electrical properties instilled to them by, e.g., metallization. To that end, sequence‐specific molecular lithography on single DNA molecules has been developed [4]. This was achieved by harnessing the exquisite homologous recombination process of the RecA protein. Sequence‐specific patterning of the metal coating of DNA molecules, localization of arbitrary labeled molecular objects at any desired dsDNA address without prior modifications, and generation of molecularly accurate stable dsDNA‐dsDNA junctions are demonstrated. The information encoded in the DNA molecules directs the lithographic process in analogy to the masks used in conventional microelectronics. The RecA protein provides the assembling capabilities, as well as the resist function. 相似文献
5.
6.
Zhi Li Kaveh Ahadi Keren Jiang Behzad Ahvazi Peng Li Anthony O.Anyia Ken Cadien Thomas Thundat 《Nano Research》2017,(5):1847-1860
Nanocellulose is a sustainable and eco-friendly nanomaterial derived from renewable biomass.In this study,we utilized the structural advantages of two types of nanocellulose and fabricated freestanding carbonized hybrid nanocellulose films as electrode materials for supercapacitors.The long cellulose nanofibrils (CNFs) formed a macroporous framework,and the short cellulose nanocrystals were assembled around the CNF framework and generated micro/mesopores.This two-level hierarchical porous structure was successfully preserved during carbonization because of a thin atomic layer deposited (ALD) Al2O3 conformal coating,which effectively prevented the aggregation of nanocellulose.These carbonized,partially graphitized nanocellulose fibers were interconnected,forming an integrated and highly conductive network with a large specific surface area of 1,244 m2·g-1.The two-level hierarchical porous structure facilitated fast ion transport in the film.When tested as an electrode material with a high mass loading of 4 mg·cm-2 for supercapacitors,the hierarchical porous carbon film derived from hybrid nanocellulose exhibited a specific capacitance of 170 F.g-1and extraordinary performance at high current densities.Even at a very high current of 50 A·g-1,it retained 65% of its original specific capacitance,which makes it a promising electrode material for high-power applications. 相似文献
7.
This paper shows that shared-coin algorithms can be combined to optimize several complexity measures, even in the presence of a strong adversary. By combining shared coins of Bracha and Rachman (1991) [10] and of Aspnes and Waarts (1996) [7], this yields a shared-coin algorithm, and hence, a randomized consensus algorithm, with O(nlog2n) individual work and O(n2logn) total work, using single-writer registers. This improves upon each of the above shared coins (where the former has a high cost for individual work, while the latter reduces it but pays in the total work), and is currently the best for this model. 相似文献
8.
This paper focuses on the detection of objects with a Lambertian surface under varying illumination and pose. We offer to apply a novel detection method that proceeds by modeling the different illuminations from a small number of images in a training set; this automatically voids the illumination effects, allowing fast illumination invariant detection, without having to create a large training set. It is demonstrated that the method “fits in” nicely with previous work about modeling the set of object appearances under varying illumination. In the experiments, an object was correctly detected under image plane rotations in a 45° range, and a wide variety of different illuminations, even when significant shadows were present. 相似文献
9.
利用傅里叶变换红外光谱仪(FTIR)在线追踪聚乙烯基苄基氯(PVBCl)与N,N,N′,N′-四甲基-1,6-己二胺(TMHDA)的交联反应历程,考察了反应时间与温度对交联程度的影响.实验结果表明,随着反应时间的延长,交联程度先迅速增大,而后趋于平缓直至不变;反应温度越高,交联程度越大.对反应进行动力学的研究计算结果显示,该交联反应的反应级数n=4,表观活化能Ea=97.2kJ/mol. 相似文献
10.
He Shuilong Chen Keren Xu Enyong Ye Mingsong Wang Yanxue 《Journal of Mechanical Science and Technology》2021,35(10):4329-4341
Journal of Mechanical Science and Technology - This article introduces a rigid-flexible coupling calculation model based on a multi-platform integrated method to analyze and optimize the cab... 相似文献