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多字体多字号印刷汉字识别方法的研究 被引量:3
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作者 崔国伟 舒文豪 李仲荣 《中文信息学报》 CSCD 1990年第3期57-62,共6页
本文对多体多字号印刷汉字识别的方法进行了研究,本文提出的方法是首先对不同字号印刷汉字进行归一化处理,再抽取汉字四周笔端数特征、改进粗外围特征、笔划穿插次数特征和投影WALSH变换特征,然后对组合特征进行多级分共识别。实验在IBM... 本文对多体多字号印刷汉字识别的方法进行了研究,本文提出的方法是首先对不同字号印刷汉字进行归一化处理,再抽取汉字四周笔端数特征、改进粗外围特征、笔划穿插次数特征和投影WALSH变换特征,然后对组合特征进行多级分共识别。实验在IBM-PC/AT微型机上进行,结果表明,实验系统在识别实际印刷文本时识别率大于98%。 展开更多
关键词 多体字 号印刷 识别
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Numerical Analysis of Multilayer Waveguides Using Effective Refractive Index Method 被引量:1
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作者 GAOShao-Wen CAOJun-Cheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第3期327-330,共4页
With the help of the effective refractive index method we have numerically analyzed a multilayer planar waveguide structure and calculated the propagation constants, confinement factors, and transverse electric (TE) m... With the help of the effective refractive index method we have numerically analyzed a multilayer planar waveguide structure and calculated the propagation constants, confinement factors, and transverse electric (TE) modes. A five-layer waveguide model has been provided to analyze the electro-magne tic wave propagation process. The analysis method has been applied to the 980 nm laser with active layer of GaInAs/GaInAsP strained quantum wells, GaInAsP confinement layers and GaInP cap layers. By changing the thickness of confinement layers, we obtained confinement factor as high as 95% with higher TE modes TE1 and TE2. The results are in good agreement with the experiment by A. Al-Muhanna et al. and give the new idea to enhance output power of semiconductor lasers. The analysis method can also be extended to any other slab multilayer waveguide structures, and the results are useful to the fabrication of optic-electronic devices. 展开更多
关键词 multilayer waveguides semiconductor laser
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Towards a multilingual, multimedia and multimodal digital library platform
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作者 黄铁军 田永鸿 +2 位作者 王春丽 史晓东 高文 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1188-1192,共5页
The China-US Million Book Digital Library Project (Million Book Project) is an intemational cooperation program between China and the US. However, one million digitized books are considered not to be the ultimate go... The China-US Million Book Digital Library Project (Million Book Project) is an intemational cooperation program between China and the US. However, one million digitized books are considered not to be the ultimate goal of the project, but a first step towards universal access to human knowledge. In particular, there are four challenges about the new way to analyze, process, operate, visualize and interact with digital media resource in this library. To tackle these challenges, North China Centre of Million Book Project (in Chinese Academy of Sciences) has initiated several innovative research projects in areas such as multimedia content analysis and retrieval, bilingual services, multimodal information presentation, and knowledge-based organization and services. In this keynote speech, we simply review our work in these areas, and argue that by technological cooperation with these innovation research topics, the project will develop a top-level digital library platform for the million book library. 展开更多
关键词 Digital library Million Book Project Multimedia content analysis Multilingual services Multimodal information presentation Knowledge organization
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Schematic interface of sound creation for computer animators
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作者 TONG Kam-pang Maya WONG Kam-wah 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第7期1141-1151,共11页
As an audiovisual medium, computer animations require superior image quality and professional soundtrack to lead audiences into their fascinating virtual world. Without sound, the impact of storytelling is reduced or ... As an audiovisual medium, computer animations require superior image quality and professional soundtrack to lead audiences into their fascinating virtual world. Without sound, the impact of storytelling is reduced or the story is even not under- standable. Despite the importance of sound, most animators are unfamiliar with sound editing software. Limited budget projects such as independent or student works have difficulty hiring sound professionals to create tailor-made soundtrack. Therefore, we need a suitable sound tool to express their individual ideas. In this paper, we propose an approach using schematic for both computer animation and sound. Our approach provides (1) physical simulation on sound through animation parameters and (2) a new channel for animators to add aesthetic values in sound through their experience of using schematics in existing animation software. We demonstrate our idea through several examples, such as Doppler shift, obstacle effect, importance, energetic, and sputtering effect. 展开更多
关键词 Computer animation MULTIMEDIA Digital media Schematics Physical simulation AESTHETIC Sound effects Soundtrack
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Numerical study on the flow features of U-beam inertial separator 被引量:1
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作者 陈丽华 樊建人 岑可法 《Journal of Zhejiang University Science》 CSCD 2002年第4期387-390,共4页
Detailed parametric study of three-dimensional gas-particle multiphase flow characteristics in U-beam tube bundle inertial separators was conducted by numerical simulation. The carrier phase was treated in the Euleria... Detailed parametric study of three-dimensional gas-particle multiphase flow characteristics in U-beam tube bundle inertial separators was conducted by numerical simulation. The carrier phase was treated in the Eulerian frame, the particles were tracked in the Lagrangian frame, and particle-wall collision was considered. Simulation carried out at different inflow rate and mass loading ratios revealed the pressure losses in the separators, velocity field of the gas phase, and the trajectories of particles. The study results revealed the multiphase flow-dynamic features of the separators, and the relationship between separator pressure losses and different inlet velocity. The numerical simulation can provide basis both for optimal design of impacting-inertial separator used in circulating fluidized bed boiler; and for study of gas-particle multiphase circumfluence flow. 展开更多
关键词 U-beam inertial separator Numerical simulation Dynamic features
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Turbo-Coded Modulation of EVRC Speech Encoder with Unequal Error Protection for Fading Channels
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作者 阿哈麦德 潘志文 +1 位作者 高西奇 尤肖虎 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期150-156,共7页
The Enhanced Variable Rate Codec (EVRC) is a standard for the Speech Service Option 3 for Wideband Spread Spectrum Digital System, which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Persona... The Enhanced Variable Rate Codec (EVRC) is a standard for the Speech Service Option 3 for Wideband Spread Spectrum Digital System, which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Personal Communications Systems). This paper investigated the combination of turbo codes with Unequal Error Protection (UEP) and 16-QAM modulation for EVRC codec of Rate 1 to get power and bandwidth efficient coding scheme. The results show that the UEP system outperforms the Equal Error Protection (EEP) one by 1.45 dB at BER of 10 -5. 展开更多
关键词 enhanced variable rate codec (EVRC) turbo codes unequal error protection (UEP) quadrature amplitude modulation (QAM)
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Characteristics of Digital Broadcasting Technology and Its Development Research
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作者 Mo YANG 《International Journal of Technology Management》 2014年第11期7-9,共3页
Driven by the rapid development of agricultural science and technology, many techniques have been developed rapidly, especially the development of broadcasting technology which earth-shaking changes have taken place. ... Driven by the rapid development of agricultural science and technology, many techniques have been developed rapidly, especially the development of broadcasting technology which earth-shaking changes have taken place. The advent of digital broadcasting technology makes the broadcast technology enter a new stage. With its low energy consumption and large coverage area, digital broadcasting technology was widely welcomed by the broadcast television industry. This paper analyzes digital audio broadcasting, multimedia digital broadcasting and digital AM broadcasting, and further concretely elaborates the application prospects of digital broadcasting technology. 展开更多
关键词 shock digital broadcasting TECHNOLOGY CHARACTERISTICS APPLICATION
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Technical features in the Portal to CADAL
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作者 吴江琴 庄越挺 潘云鹤 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1249-1257,共9页
China-America Digital Academic Library Project (CADAL) is a collaborative project between universities and institutes in China and the USA, which aims to provide universal access to large scale digital resources and e... China-America Digital Academic Library Project (CADAL) is a collaborative project between universities and institutes in China and the USA, which aims to provide universal access to large scale digital resources and explore the ways of applying multimedia and virtual reality technologies to digital library. The distinct characteristic of the resources in CADAL is that it not only contains one million digital books of different languages, but also contains Terabyte level multimedia resources (image, video, and so on), which are utilized for education and research purposes. So, in the Portal to CADAL, both the traditional services of browsing and searching of digital books, and the services of quickly retrieving and structurally browsing of multimedia documents should be provided. In addition, the services of visual presentation of retrieved results are required too. In this paper, the underlying novel multimedia retrieval methods as well as visualization techniques, which are used in the CADAL portal, are investigated. 展开更多
关键词 CADAL Video summarization Multimedia retrieval Chinese calligraphy 3-D visualization
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Digital libraries: A testbed for multimedia technology
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作者 庄越挺 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1201-1203,共3页
A distinguishing feature of a digital library is that it has Terabyte volumes of multimedia resources. One challenge for researchers in the field of multimedia is to find a testbed for showing the potentials of multim... A distinguishing feature of a digital library is that it has Terabyte volumes of multimedia resources. One challenge for researchers in the field of multimedia is to find a testbed for showing the potentials of multimedia technologies such as video summarization, semantic annotation, multimedia cross indexing and retrieval, and etc. Deeper research and wider applications of digital libraries revealed their indispensable role as testbed for multimedia technologies. This paper presents challenging issues of some key techniques used in digital libraries and their specific needs for multimedia technologies. 展开更多
关键词 Digital library Multimedia technology CADAL (China-America Digital Academic Library)
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A Research for a Division of Regular Polyhedron by Rhombic Dodecahedron
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作者 Jun Hee Mun Jong Youll Park 《Journal of Mathematics and System Science》 2014年第8期569-573,共5页
Abstract:A space-filling polyhedron is a polyhedron which 'tile' space, analogous to the way of certain polygons tiled the plane. The cube is the unique space-filling platonic solid. If we make line connections the... Abstract:A space-filling polyhedron is a polyhedron which 'tile' space, analogous to the way of certain polygons tiled the plane. The cube is the unique space-filling platonic solid. If we make line connections the center with the vertices in the certain cube, the cube is divided into six pyramids. And if we glued six pyramids to the faces of the cube, we obtain a 'rhombic dodecahedron'. Since cubes are packing a space, rhombic dodecahedra are also space-filling polyhedra and a rhombic dodecahedron is divided into two regular tetrahcdra and one regular octahedron. In this study, we present how rhombic dodecahedron can be split into tetrahedra and octahedron. In this process, we can research a variety of divisions of regular polyhedron. 展开更多
关键词 Rhombic dodecahedron CUBE TETRAHEDRON octahedron.
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Thermal Conductivity of Complex Plasmas Using Novel Evan-Gillan Approach
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作者 Aamir Shahzad Syed Irfan Haider +3 位作者 Muhammad Kashif Muhammad Shahzad Shifa Tariq Munir Mao-Gang He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第6期704-710,共7页
The thermal conductivity of complex fluid materials (dusty plasmas) has been explored through novel Evan-Gillan homogeneous non-equilibrium molecular dynamic (HNEMD) algorithm. The thermal conductivity coefficient... The thermal conductivity of complex fluid materials (dusty plasmas) has been explored through novel Evan-Gillan homogeneous non-equilibrium molecular dynamic (HNEMD) algorithm. The thermal conductivity coefficient obtained from HNEMD is dependent on various plasma parameters (T,k). The proposed algorithm gives accurate results with fast convergence and small size effect over a wide range of plasma parameters. The cross microscopic heat energy current is discussed in association with variation of temperature (1/Г) and external perturbations (Pz). The thermal conductivity obtained from HNEMD simulations is found to be very good agreement and more reliable than previously known numerical techniques of equilibrium molecular dynarnic, nonequilibrium molecular dynamic simulations. Our new investigations point to an effective conclusion that the thermal conductivity of complex dusty plasmas is dependent on an extensive range of plasma coupling (P) and screening parameter (k) and it varies by the alteration in these parameters. It is also shown that a different approach is used for computations of thermal conductivity in 2D complex plasmas and can be appropriate method for behaviors of complex systems. 展开更多
关键词 complex dusty plasma homogenous nonequilibrium molecular dynamics canonical ensemble scaling law thermal conductivity Yukawa liquids
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Bingham Flows in Periodic Domains of Infinite Length
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作者 Patrizia DONATO Sorin MARDARE Bogdan VERNESCU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2018年第2期183-200,共18页
The Bingham fluid model has been successfully used in modeling a large class of non-Newtonian fluids. In this paper, the authors extend to the case of Bingham fluids the results previously obtained by Chipot and Marda... The Bingham fluid model has been successfully used in modeling a large class of non-Newtonian fluids. In this paper, the authors extend to the case of Bingham fluids the results previously obtained by Chipot and Mardare, who studied the asymptotics of the Stokes flow in a cylindrical domain that becomes unbounded in one direction, and prove the convergence of the solution to the Bingham problem in a finite periodic domain, to the solution of the Bingham problem in the infinite periodic domain, as the length of the finite domain goes to infinity. As a consequence of this convergence, the existence of a solution to a Bingham problem in the infinite periodic domain is obtained, and the uniqueness of the velocity field for this problem is also shown. Finally, they show that the error in approximating the velocity field in the infinite domain with the velocity in a periodic domain of length 2l has a polynomial decay in , unlike in the Stokes case (see [Chipot, M. and Mardare, S., Asymptotic behaviour of the Stokes problem in cylinders becoming unbounded in one direction, Journal de Mathgmatiques Pures et Appliqudes, 90(2), 2008, 133-159]) where it has an exponential decay. This is in itself an important result for the numerical simulations of non-Newtonian flows in long tubes. 展开更多
关键词 Bingham fluids Variational inequalities
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