A novel algorithm for image edge detection is presented. This algorithm combines the nonsubsampled contourlet transform and the mathematical morphology. First, the source image is decomposed by the nonsubsampled conto...A novel algorithm for image edge detection is presented. This algorithm combines the nonsubsampled contourlet transform and the mathematical morphology. First, the source image is decomposed by the nonsubsampled contourlet transform into multi-scale and multi-directional subbands. Then the edges in the high-frequency and low-frequency sub-bands are respectively extracted by the dualthreshold modulus maxima method and the mathematical morphology operator. Finally, the edges from the high- frequency and low-frequency sub-bands are integrated to the edges of the source image, which are refined, and isolated points are excluded to achieve the edges of the source image. The simulation results show that the proposed algorithm can effectively suppress noise, eliminate pseudo-edges and overcome the adverse effects caused by uneven illumination to a certain extent. Compared with the traditional methods such as LoG, Sobel, and Carmy operators and the modulus maxima algorithm, the proposed method can maintain sufficient positioning accuracy and edge details, and it can also make an improvement in the completeness, smoothness and clearness of the outline.展开更多
Anton Webem＇s （1883-1945） largest project of the early the 1930s, the Concerto for Nine （solo） Instrument＇s Op. 24, is for flute, oboe, clarinet, horn, trumpet, trombone, violin, viola, and piano. This serial w...Anton Webem＇s （1883-1945） largest project of the early the 1930s, the Concerto for Nine （solo） Instrument＇s Op. 24, is for flute, oboe, clarinet, horn, trumpet, trombone, violin, viola, and piano. This serial work＇s analysis became almost as famous as the concerto itself. Highly economical, short, concentrated and free relationship between the intervals take over from tonality as the main organizational principle ＂pontillistic＂ style. The clear and transparent frame ＂Klangfarbenmelodie＂, is a row, that was distributed among different instruments. So that, several notes can be heard in the same timbre. Like most of Webern works, there are quiet special effects like a whisper, string harmonics, pizzicato, muting, and athematic intevalic cells as the basic structural element. Concerto for Nine Instruments has succeeding series of twelve-tone works. Webern worked for a long time on the Concerto＇s raw, trying to arrive at an equivalent to the Latin word-square palindrome which reads the same left to right from the top, right to left from the bottom, downwards from the top left, or upwards from the bottom right.SATOR AREPO TENET OPERA ROTAS展开更多
The paper design a double eccentric mass driven spherical robot, the ball is also subject to eccentric force and inertia force that generate by internal drive units in movement. Due to the unique spherical shell, the ...The paper design a double eccentric mass driven spherical robot, the ball is also subject to eccentric force and inertia force that generate by internal drive units in movement. Due to the unique spherical shell, the robot in the dynamic state transition process, Friction cannot offset the robot motion state change due to internal driving motion error of small units. In order to make linear movement of the spherical robot that can smooth start, stop and speed control, the paper design a method for linear motion driven spherical robot with double eccentric mass control. The improved driving eccentric mass of robot total mass ratio is larger, that can provide the eccentric torque and inertia moment more, the robot has higher motion velocity.展开更多
The title complex, mercury bridged biferrocene trinuclear complex Hg(FcL)2. Bis (S-methyl-N- (1-ferrocenyl-1-methyl) methylenedithiocarbazate) mercury,Crystallizes in space group Pbca with a =19. 510 (4), b=19. 921 (5...The title complex, mercury bridged biferrocene trinuclear complex Hg(FcL)2. Bis (S-methyl-N- (1-ferrocenyl-1-methyl) methylenedithiocarbazate) mercury,Crystallizes in space group Pbca with a =19. 510 (4), b=19. 921 (5), c=15. 581 (3)A. V=6095(3) A, Z=8,M.=863. 12, Dc=1.881 g/cm3; u=19. 24 cm-1 and F(000) = 3376. The final refinement of 2455 observed reflections is converged with R= 0. 043 and Rw=0.047. X-ray crystal structure analysis revealed that the coordinationgeometry of Hg atom is a distorted tetrahedron with two Hg-N bonds and two Hg- S bonds. The Schiff-base ligand loses a proton from its tautomeric thiol form and is cryordianted to the Hg aotm uia the mercapto sulphur and the β-nitrogen atoms.展开更多
An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisind...An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisindole scaffolds containing an all-carbon quaternary stereogenic center were obtained in high yields and with excellent enantioselectivities. 3,3’-Bisindoles are valuable synthetic intermediates, the employment of which led to formal total syntheses of(+)-Chimonanthine,(+)-Folicanthine and(-)-Calycanthine, as well as facile creation of useful pyrrolidinoindoline core structure.展开更多
基金The National Key Technologies R&D Program during the 12th Five-Year Period of China(No.2012BAJ23B02)Science and Technology Support Program of Jiangsu Province(No.BE2010606)
文摘A novel algorithm for image edge detection is presented. This algorithm combines the nonsubsampled contourlet transform and the mathematical morphology. First, the source image is decomposed by the nonsubsampled contourlet transform into multi-scale and multi-directional subbands. Then the edges in the high-frequency and low-frequency sub-bands are respectively extracted by the dualthreshold modulus maxima method and the mathematical morphology operator. Finally, the edges from the high- frequency and low-frequency sub-bands are integrated to the edges of the source image, which are refined, and isolated points are excluded to achieve the edges of the source image. The simulation results show that the proposed algorithm can effectively suppress noise, eliminate pseudo-edges and overcome the adverse effects caused by uneven illumination to a certain extent. Compared with the traditional methods such as LoG, Sobel, and Carmy operators and the modulus maxima algorithm, the proposed method can maintain sufficient positioning accuracy and edge details, and it can also make an improvement in the completeness, smoothness and clearness of the outline.
文摘Anton Webem＇s （1883-1945） largest project of the early the 1930s, the Concerto for Nine （solo） Instrument＇s Op. 24, is for flute, oboe, clarinet, horn, trumpet, trombone, violin, viola, and piano. This serial work＇s analysis became almost as famous as the concerto itself. Highly economical, short, concentrated and free relationship between the intervals take over from tonality as the main organizational principle ＂pontillistic＂ style. The clear and transparent frame ＂Klangfarbenmelodie＂, is a row, that was distributed among different instruments. So that, several notes can be heard in the same timbre. Like most of Webern works, there are quiet special effects like a whisper, string harmonics, pizzicato, muting, and athematic intevalic cells as the basic structural element. Concerto for Nine Instruments has succeeding series of twelve-tone works. Webern worked for a long time on the Concerto＇s raw, trying to arrive at an equivalent to the Latin word-square palindrome which reads the same left to right from the top, right to left from the bottom, downwards from the top left, or upwards from the bottom right.SATOR AREPO TENET OPERA ROTAS
文摘The paper design a double eccentric mass driven spherical robot, the ball is also subject to eccentric force and inertia force that generate by internal drive units in movement. Due to the unique spherical shell, the robot in the dynamic state transition process, Friction cannot offset the robot motion state change due to internal driving motion error of small units. In order to make linear movement of the spherical robot that can smooth start, stop and speed control, the paper design a method for linear motion driven spherical robot with double eccentric mass control. The improved driving eccentric mass of robot total mass ratio is larger, that can provide the eccentric torque and inertia moment more, the robot has higher motion velocity.
文摘The title complex, mercury bridged biferrocene trinuclear complex Hg(FcL)2. Bis (S-methyl-N- (1-ferrocenyl-1-methyl) methylenedithiocarbazate) mercury,Crystallizes in space group Pbca with a =19. 510 (4), b=19. 921 (5), c=15. 581 (3)A. V=6095(3) A, Z=8,M.=863. 12, Dc=1.881 g/cm3; u=19. 24 cm-1 and F(000) = 3376. The final refinement of 2455 observed reflections is converged with R= 0. 043 and Rw=0.047. X-ray crystal structure analysis revealed that the coordinationgeometry of Hg atom is a distorted tetrahedron with two Hg-N bonds and two Hg- S bonds. The Schiff-base ligand loses a proton from its tautomeric thiol form and is cryordianted to the Hg aotm uia the mercapto sulphur and the β-nitrogen atoms.
基金Yixin Lu thanks the Singapore National Research Foundation,Prime Minister’s Office for the NRF Investigatorship Award(R-143-000-A15-281)Financial supports from the National University of Singapore(R-143-000-695-114 and C-141-000-092-001)the National Natural Science Foundation of China(21672158)are also gratefully acknowledged.
文摘An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisindole scaffolds containing an all-carbon quaternary stereogenic center were obtained in high yields and with excellent enantioselectivities. 3,3’-Bisindoles are valuable synthetic intermediates, the employment of which led to formal total syntheses of(+)-Chimonanthine,(+)-Folicanthine and(-)-Calycanthine, as well as facile creation of useful pyrrolidinoindoline core structure.
