This paper presents the construction of two kinds of focusing measure operators defined in wavelet domain. One mechanism is that the Discrete Wavelet Transform （DWT） coefficients in high frequency subbands of in-foc...This paper presents the construction of two kinds of focusing measure operators defined in wavelet domain. One mechanism is that the Discrete Wavelet Transform （DWT） coefficients in high frequency subbands of in-focused image are higher than those of defocused one. The other mechanism is that the autocorrelation of an in-focused image filtered through Continuous Wavelet Transform （CWT） gives a sharper profile than blurred one does. Wavelet base, scaling factor and form to get the sum of high frequency energy are the key factors in constructing the operator. Two new focus measure operators are defined through the autofocusing experiments on the micro-vision system of the workcell for micro-aligmnent. The performances of two operators can be quantificationally evaluated through the comparison with two spatial domain operators--Brenner Function （BF） and Squared Gradient Function （SGF）. The focus resolution of the optimized DWT-based operators is 14% higher than that of BF and its computational cost is 52% approximately lower than BF＇s. The focus resolution of the optimized CWT-based operators is 41% lower than that of SGF whereas its computational cost is approximately 36% lower than SGF＇s. It shows that the wavelet based autofocus measure functions can be practically used in micro-vision applications.展开更多
Due to limited depth-of-field of digital single-lens reflex cameras,the scene content within a limited distance from the imaging plane remains in focus while other objects closer to or further away from the point of f...Due to limited depth-of-field of digital single-lens reflex cameras,the scene content within a limited distance from the imaging plane remains in focus while other objects closer to or further away from the point of focus appear as blurred(out-of-focus)in the image.Multi-Focus Image Fusion can be used to reconstruct a fully focused image from two or more partially focused images of the same scene.In this paper,a new Fuzzy Based Hybrid Focus Measure(FBHFM)for multi-focus image fusion has been proposed.Optimal block size is very critical step for multi-focus image fusion.Particle Swarm Optimization(PSO)algorithm has been used to find optimal size of the block of the images for extraction of focus measure features.After finding optimal blocks,three focus measures Sum of Modified Laplacian,Gray Level Variance and Contrast Visibility has been extracted and combined these focus measures by using intelligent fuzzy technique.Fuzzy based hybrid intelligent focus values were estimated using contrast visibility measure to generate focused image.Different sets of multi-focus images have been used in detailed experimentation and compared the results with state-of-the-art existing techniques such as Genetic Algorithm(GA),Principal Component Analysis(PCA),Laplacian Pyramid discrete wavelet transform(DWT),and aDWT for image fusion.It has been found that proposed method performs well as compare to existing methods.展开更多
Western Canada’s oil sands hold the third-largest hydrocarbon deposits in the world.Bitumen,a very heavy petroleum,is currently recovered by surface mining with warm water or in situ.Recovery processes that use organ...Western Canada’s oil sands hold the third-largest hydrocarbon deposits in the world.Bitumen,a very heavy petroleum,is currently recovered by surface mining with warm water or in situ.Recovery processes that use organic solvents are being developed to reduce water usage and tailings production.While solvent-based methods can effectively extract bitumen,removal of residual fine solids from diluted bitumen product(DBP)to meet the pipeline transport requirement of<0.5 wt%solids and water in DBP remains a major challenge.We propose a novel area of application of polymer flocculants for fine solids removal from DBP.In principle,polymer flocculants can be applied to help remove these residual solids in conjunction with physical separation processes to increase process effectiveness and energy efficiency.Several polymers are selected and screened for flocculation behavior using kaolinite suspended in DBP and toluene,as a model system.Focused beam reflectance measurements and force tensiometer techniques are used to determine flocculation and sedimentation in DBP.The observed flocculation and sedimentation rate enhancements indicate that the polymers tested have only minor effects,providing opportunities for advanced polymer development.These findings exemplify the challenges in identifying polymers that may be effective as flocculants in heavy petroleum media.展开更多
In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical ape...In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical aperture （NA） objective lens reflected by the sample under study, the Brewster angle is found. Employing a high NA objective lens allows the measurement of multiple angles of incidence from 0° to 64° in a single shot. The refractive index of the sample is estimated using the measured Brewster angle. The experimental results are compared with the theoretical images computed with the Fresnel theory, and a good agreement is obtained.展开更多
基金Hi-Tech Research and Development Program of China(2002AA404460,2004AA404260)National "15","211 Project" ofChina
文摘This paper presents the construction of two kinds of focusing measure operators defined in wavelet domain. One mechanism is that the Discrete Wavelet Transform （DWT） coefficients in high frequency subbands of in-focused image are higher than those of defocused one. The other mechanism is that the autocorrelation of an in-focused image filtered through Continuous Wavelet Transform （CWT） gives a sharper profile than blurred one does. Wavelet base, scaling factor and form to get the sum of high frequency energy are the key factors in constructing the operator. Two new focus measure operators are defined through the autofocusing experiments on the micro-vision system of the workcell for micro-aligmnent. The performances of two operators can be quantificationally evaluated through the comparison with two spatial domain operators--Brenner Function （BF） and Squared Gradient Function （SGF）. The focus resolution of the optimized DWT-based operators is 14% higher than that of BF and its computational cost is 52% approximately lower than BF＇s. The focus resolution of the optimized CWT-based operators is 41% lower than that of SGF whereas its computational cost is approximately 36% lower than SGF＇s. It shows that the wavelet based autofocus measure functions can be practically used in micro-vision applications.
文摘Due to limited depth-of-field of digital single-lens reflex cameras,the scene content within a limited distance from the imaging plane remains in focus while other objects closer to or further away from the point of focus appear as blurred(out-of-focus)in the image.Multi-Focus Image Fusion can be used to reconstruct a fully focused image from two or more partially focused images of the same scene.In this paper,a new Fuzzy Based Hybrid Focus Measure(FBHFM)for multi-focus image fusion has been proposed.Optimal block size is very critical step for multi-focus image fusion.Particle Swarm Optimization(PSO)algorithm has been used to find optimal size of the block of the images for extraction of focus measure features.After finding optimal blocks,three focus measures Sum of Modified Laplacian,Gray Level Variance and Contrast Visibility has been extracted and combined these focus measures by using intelligent fuzzy technique.Fuzzy based hybrid intelligent focus values were estimated using contrast visibility measure to generate focused image.Different sets of multi-focus images have been used in detailed experimentation and compared the results with state-of-the-art existing techniques such as Genetic Algorithm(GA),Principal Component Analysis(PCA),Laplacian Pyramid discrete wavelet transform(DWT),and aDWT for image fusion.It has been found that proposed method performs well as compare to existing methods.
文摘Western Canada’s oil sands hold the third-largest hydrocarbon deposits in the world.Bitumen,a very heavy petroleum,is currently recovered by surface mining with warm water or in situ.Recovery processes that use organic solvents are being developed to reduce water usage and tailings production.While solvent-based methods can effectively extract bitumen,removal of residual fine solids from diluted bitumen product(DBP)to meet the pipeline transport requirement of<0.5 wt%solids and water in DBP remains a major challenge.We propose a novel area of application of polymer flocculants for fine solids removal from DBP.In principle,polymer flocculants can be applied to help remove these residual solids in conjunction with physical separation processes to increase process effectiveness and energy efficiency.Several polymers are selected and screened for flocculation behavior using kaolinite suspended in DBP and toluene,as a model system.Focused beam reflectance measurements and force tensiometer techniques are used to determine flocculation and sedimentation in DBP.The observed flocculation and sedimentation rate enhancements indicate that the polymers tested have only minor effects,providing opportunities for advanced polymer development.These findings exemplify the challenges in identifying polymers that may be effective as flocculants in heavy petroleum media.
基金GLM and VMRB acknowledge CONACYT-M6xico for the scholarship 353317 and 394565, respectively, which were given to them to do their graduate studies.
文摘In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical aperture （NA） objective lens reflected by the sample under study, the Brewster angle is found. Employing a high NA objective lens allows the measurement of multiple angles of incidence from 0° to 64° in a single shot. The refractive index of the sample is estimated using the measured Brewster angle. The experimental results are compared with the theoretical images computed with the Fresnel theory, and a good agreement is obtained.
