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91.
92.
In this paper, we present a gradient domain image fusion framework based on the Markov Random Field (MRF) fusion model. In this framework, the salient structures of the input images are fused in the gradient domain, then the final fused image is reconstructed by solving a Poisson equation which forces the gradients of the fused image to be close to the fused gradients. To fuse the structures in the gradient domain, an effective MRF-based fusion model is designed based on both the per-pixel fusion rule defined by the local saliency and also the smoothness constraints over the fusion weights, which is optimized by graph cut algorithm. This MRF-based fusion model enables the accurate estimation of region-based fusion weights for the salient objects or structures. We apply this method to the applications of multi-sensor image fusion, including infrared and visible image fusion, multi-focus image fusion and medical image fusion. Extensive experiments and comparisons show that the proposed fusion model is able to better fuse the multi-sensor images and produces high-quality fusion results compared with the other state-of-the-art methods. 相似文献
93.
孙超 《计算机光盘软件与应用》2011,(10)
SSO(Single Sign On)是并购整合后期的技术整合中必须要实现的一个功能,而通常不能直接将并购者的用户数据与被并购者的用户数据直接合并,本文着重分析了在实现SSO数据整合中可能存在的问题,并针对各个问题给出了初步的解决方案. 相似文献
94.
95.
上期中,我们为大家带来了早期显卡的发展情况——显卡从无到有,从2D到3D,从性能到性能变强,其中的故事也非常的精彩。在经历了早期群雄逐鹿的时代后,显卡市场逐渐呈NVIDIA和ATI两分天下的局面。 相似文献
96.
Since the harmonic components in the signal to be analyzed are uncertain and diverse, it is difficult to make the sampling frequency and the signal length be harmonically related to the component frequencies included in the signal, and the leakage is produced in the discrete Fourier transform. Based on the definition of the Herfindahl index in economics, the spectrum concentration can be defined and computed. The appropriate number of points can be decided according to the peak location of the spectrum concentration. The method and the examples are specified in detail in the paper. 相似文献
97.
Wen-Ke Wang Hui Zhang Hyungjun Park Jun-Hai Yong Jean-Claude Paul Jia-Guang Sun 《Computer aided design》2008,40(10-11):999-1008
A new algorithm for reducing control points in lofted surface interpolation to rows of data points is presented in this paper. The key step of surface lofting is to obtain a set of compatible B-spline curves interpolating each row. Given a set of points and their parameterization, a necessary and sufficient condition is proposed to determine the existence of interpolating B-spline curves defined on a given knot vector. Based on this condition, we first properly construct a common knot vector that guarantees the existence of interpolating B-spline curves to each row of points. Then we calculate a set of interpolating B-spline curves defined on the common knot vector by energy minimization. Using this method, fewer control points are employed while maintaining a visually pleasing shape of the lofted surface. Several experimental results demonstrate the usability and quality of the proposed method. 相似文献
98.
构造Internet上的专家系统对扩大知识的共享范围具有重要意义。本文提出的一种基于可拓学的,使用Java开发方法,基于B/S程序架构,使得基于Web的专家系统能够充分发挥Java的高移植性、高扩展性的特点,而且可以发挥可拓规则的扩展性,以及动态性的特点。 相似文献
99.
100.
Shiyu Huang Yuan Chang Zhuwei Li Jiaqi Cao Yurou Song Junfeng Gao Licheng Sun Jungang Hou 《Advanced functional materials》2023,33(21):2211631
Photoredox catalysis is a green solution for organics transformation and CO2 conversion into valuable fuels, meeting the challenges of sustainable energy and environmental concerns. However, the regulation of single-atomic active sites in organic framework not only influences the photoredox performance, but also limits the understanding of the relationship for photocatalytic selective organic conversion with CO2 valorization into one reaction system. As a prototype, different single-atomic metal (M) sites (M2+ = Fe2+, Co2+, Ni2+, Cu2+, and Zn2+) in hydrogen-bonded organic frameworks (M-HOF) backbone with bridging structure of metal-nitrogen are constructed by a typical “two-in-one” strategy for superior photocatalytic C N coupling reactions integrated with CO2 valorization. Remarkably, Zn-HOF achieves 100% conversion of benzylamine oxidative coupling reactions, 91% selectivity of N-benzylidenebenzylamine and CO2 conversion in one photoredox cycle. From X-ray absorption fine structure analysis and density functional theory calculations, the superior photocatalytic performance is attributed to synergic effect of atomically dispersed metal sites and HOF host, decreasing the reaction energy barriers, enhancing CO2 adsorption and forming benzylcarbamic acid intermediate to promote the redox recycle. This work not only affords the rational design strategy of single-atom active sites in functional HOF, but also facilitates the fundamental insights upon the mechanism of versatile photoredox coupling reaction systems. 相似文献