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61.
The paper presents a novel blind watermarking scheme for image copyright protection, which is developed in the discrete wavelet transform (DWT) and is based on the singular value decomposition (SVD) and the support vector regression (SVR). Its embedding algorithm hides a watermark bit in the low–low (LL) subband of a target non-overlap block of the host image by modifying a coefficient of U component on SVD version of the block. A blind watermark-extraction is designed using a trained SVR to estimate original coefficients. Subsequently, the watermark bit can be computed using the watermarked coefficient and its corresponding estimate coefficient. Additionally, the particle swarm optimization (PSO) is further utilized to optimize the proposed scheme. Experimental results show the proposed scheme possesses significant improvements in both transparency and robustness, and is superior to existing methods under consideration here.  相似文献   
62.
新的现代化技术服务于教育是高职院校现代教育发展的必然趋势,文章系统地叙述了高职院校为进一步推动物联网在教育与教学设备监控的应用,做了不断的探索和实践,以期对高职院校的教育与教学设备监控建设工作提供一些借鉴。  相似文献   
63.
Highly conductive transparent aluminium-doped ZnO (ZnO:A1) films were successfully deposited by CW-CO2 laser-induced evaporation. Optimisation of evaporation parameters was based on laser power, substrate temperature, O2 partial pressure in the vacuum chamber and amount of Al in the ZnO source pellet. ZnO:A1 films with an electrical resistivity as low as 6.6 × 10−2Ω·cm and an optical transmission of 80% at 500nm were obtained at laser power of 15 W, substrate temperature of about 200°C, O2 partial pressure of 6—7 × 10−4 Torr and 5wt.% Al. Conductivity of ZnO films can be increased one order via Al-doping in ZnO films. The films obtained by laser-induced evaporation have compared quite favorably with the high quality films obtained by sputtering.  相似文献   
64.
The constrained blister test is investigated through finite element analysis to determine the applicabilities and the limitations of the new technique. Numerical results confirm that the strain energy release rate asymptotically approaches a constant value. These results also show that the test technique and the approximate solution for strain energy release rate are applicable for some practical cases.  相似文献   
65.
The effect of virgin, high-density polyethylene (HDPE)/recycled HDPE composition on the physical properties of the blends was investigated. The recycled HDPE was obtained from a postconsumer cycle of milk bottles. It was found that elongation at break was the mechanical property mostly affected by the content of recycled HDPE. Overall, however, the recycled HDPE from milk bottles was found to be a material with useful properties not largely different from those of virgin resin and thus could be used, at an appropriate concentration in virgin HDPE, for different applications.  相似文献   
66.
Moisture Distribution and Dewatering Efficiency for Wet Materials   总被引:3,自引:0,他引:3  
This review paper summarizes current research efforts toward a comprehensive view of wet material dewatering, considering the binding energy as the strength to hold water, and rupture energy given to remove moisture from materials.  相似文献   
67.
In order to solve the transformation problem of Bill of Materials (BOM) from engineering BOM to maintenance BOM for Maintenance, Repair and Overhaul (MRO) systems, a formal transformation model of BOM view is proposed. In this model, the intermediate component, inherited component, virtual component are defined in the specific maintenance management domain, and the transformation process from engineering BOM to maintenance BOM is discussed through feature recognition methods and rules. The proposed transformation model has been developed and deployed in an MRO system for a steel manufacturing enterprise.  相似文献   
68.
作者应用前 S_1、前 S_2和 HBsAg/a 单克隆抗体,用免疫斑点法(Immuno-spot)检测同一批的乙肝表面抗原分别经加热灭活和三步化学灭活后的前 S_1和前 S_2蛋白保留情况,比较了两种工艺对前 S_1和前 S_2蛋白的影响。结果表明;加热灭活可保留前 S_1和前 S_2蛋白,三步化学灭活使前 S_1和前 S_2蛋白丢失,从抗原组成上看,加热灭活后的抗原更接近自然抗原。首次报告了含有前 S_1蛋白的乙肝疫苗,并对前 S_1和前 S_2蛋白在乙肝血源疫苗中的可能作用进行了讨论。  相似文献   
69.
Thermotropic polyester carbonates derived from t-butylhydroquinone, methylhydroquinone, diphenyl terephthalate, and diphenyl carbonate in the molar ratio of 50 : 50 : 55 : 45; 50 : 50 : 57.5 : 5 : 42.5 and 50 : 50 : 60 : 40 can be injection molded successfully from temperatures 10°C below melting to 30–40°C above melting. Normally the best molding temperatures are 10–20°C above melting. If the molding conditions are controlled properly, tensile strengths as high as 1.8 × 104 psi, tensile moduli as high as 7.4 × 105 psi, and flex moduli as high as 1.1 × 106 psi can be obtained.  相似文献   
70.
近红外分析共享平台中的采集工作流是一个以数据为中心的工作流。对系统中复杂采集工作流的跳转执行过程进行了详细分析,针对自由工作流跳转造成的数据和状态不一致性的问题,提出了一个任务执行优先关系算法,计算采集工作流中各个活动任务执行次序关系值,并构造一个执行次序关系树,记录各任务活动的状态信息;在流程回退、撤销、跳转时保证了数据和状态的一致性,较好地实现了跨任务活动的跳转。应用结果表明,此算法能够正确高效地实现复杂流程的跳转。  相似文献   
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