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191.
192.
Watermarking on 3D mesh based on spherical wavelet transform 总被引:1,自引:0,他引:1
In this paper we propose a robust watermarking algorithm for 3D mesh. The algorithm is based on spherical wavelet transform. Our basic idea is to decompose the original mesh into a series of details at different scales by using spherical wavelet transform; the watermark is then embedded into the different levels of details. The embedding process includes: global sphere parameterization, spherical uniform sampling, spherical wavelet forward transform, embedding watermark, spherical wavelet inverse transform, and at last resampling the mesh watermarked to recover the topological connectivity of the original model. Experiments showed that our algorithm can improve the capacity of the watermark and the robustness of watermarking against attacks. 相似文献
193.
Science Letters:Synergetic effects for p-nitrophenol abatement using a combined activated carbon adsorption-electrooxidation process 总被引:1,自引:0,他引:1
A novel fluidized electrochemical reactor that integrated advanced electrochemical oxidation with activated carbon (AC) fluidization in a single cell was developed to model pollutant p-nitrophenol (PNP) abatement. AC fluidization could enhance COD removal by 22%-30%. In such a combined process, synergetic effects on PNP and COD removal was found, with their removal rate being enhanced by 137.8% and 97.8%, respectively. AC could be electrochemically regenerated and reused, indicating the combined process would be promising for treatment of biorefractory organic pollutants. 相似文献
194.
Rough set axiomatization is one aspect of rough set study to characterize rough set theory using dependable and minimal axiom groups. Thus, rough set theory can be studied by logic and axiom system methods. The classic rough set theory is based on equivalent relation, but rough set theory based on reflexive and transitive relation (called quasi-ordering) has wide applications in the real world. To characterize topological rough set theory, an axiom group named RT, consisting of 4 axioms, is proposed. It is proved that the axiom group reliability in characterizing rough set theory based on similar relation is reasonable. Simultaneously, the minimization of the axiom group, which requires that each axiom is an equation and each is independent, is proved. The axiom group is helpful for researching rough set theory by logic and axiom system methods. 相似文献
195.
WANG Xichao DAI Bojie CHEN Dayuan LIU Zelong LIU Weimin & DUAN Enkui State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China Correspondence should be addressed to Duan Enkui 《科学通报(英文版)》2003,48(18):1956-1961
Pregnancy between different species is one of the key steps to interspecific somatic cell cloning. Although interspecific clone embryos have been constructed, they could not develop to birth after being transferred to recipi-ents. In order to clarify the mechanism of this phenomenon, interfamily pregnancy between golden hamste (Mesocricetus auratus) and mouse (Mus musculus) was studied. Co-culture results indicated that the adhesion ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 12, 24, 48 and 72 h after co-culture were all significantly lower than those of mouse blastocysts. The outgrowth ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 48, 72 h after co-culture were both significantly lower than those of mouse blastocysts (P < 0.01). Golden hamster抯 blastula could be implanted and develop to D 11 of pregnancy after being transferred to mouse uterus (the 7th day after embryo transfer). Compared to the transfer of mouse embryo to mouse uterus, the successful ratio of interfamily embryo transfer was lower and the bulk of fetus was smaller than that of intraspecific fetus. Compared to intraspecific preg-nancy of mouse, the remote decidual tissue of interfamily pregnancy on D8 is looser. At the same time, expressions of CD57 and CD 68 in remote deciduas were both higher than those in the secondary deciduas in both intraspecific and interfamily pregnancy. However, expressions of the two molecules in interfamily pregnancy were lower than those in intraspecific pregnancy. These results showed that interfam-ily pregnancy could be established between golden hamster and mouse. But the development of fetus in interfamily pregnancy was slower than that in intraspecific pregnancy. The expression difference of CD57 and CD68 indicates the difference of immunoreaction between interfamily and in-traspecific pregnancy, which may be one of the reasons lead-ing to interfamily pregnancy termination. 相似文献
196.
197.
绿色技术创新政策的国际经验对福建的借鉴与启示 总被引:2,自引:0,他引:2
绿色技术创新是福建可持续发展的重要途径。本文首先对美国、日本和欧盟的绿色技术创新的法律政策、财政税收支持政策、绿色采购政策和教育政策等四个方面进行深入分析,并与福建进行对比分析,找出目前福建在绿色技术创新政策的不足与发展方向,希望对福建省制订和完善绿色技术创新政府以及更好地推进资源节约型和环境最好型社会的建设具有借鉴意义。 相似文献
198.
通过THERMOMASTER-Z型热/力模拟试验机对CSP生产线上冷轧冲压基板(SPHD)进行了热变形实验,建立了该钢种的临界应变模型以及流动应力-应变模型;分析了试验过程中工艺参数对临界应变、流动应力的影响。结果表明,变形温度、变形速率是影响临界应变的主要因素,当热变形达到临界应变时,将发生动态再结晶,同时造成变形抗力的波动。 相似文献
199.
观赏植物无土栽培的研究进展 总被引:2,自引:1,他引:2
综述了国内外近10年来观赏植物无土栽培的研究进展和应用情况。介绍了对无土栽培中栽培基质、营养液配方和植物生长发育规律的研究情况,并就观赏植物无土栽培的前景进行了展望。 相似文献
200.